Engine will not shut off: ignition relay issues

[RDS]

Euro spec carb 1500 (late) car.

After some success fitting the Panda light switch and 4-relay set up and putting a relay in to the electric fuel pump circuit (instead of the mechanical pump), I had a failure relating to the fitting of an ignition relay, with which I’d like some help. I wanted to take yet more stress off the ignition switch that I had just rebuilt.

By way of clarification, I adapted a simple ignition relay scheme to suit what I had available, what was easily accessible and the space available in the fusebox, (which means that I was not necessarily able to use the proper polarity connection scheme for the relay). Therefore:

Terminal 87 is fed by +12v from the busbar in the fusebox as the permanent live;

Terminal 30 then feeds +12v to the terminal on the rear of the fuseblock, (which was formerly occupied by the red/black wire which goes to the ignition switch (see below)) which connects internally in the fuseblock to the +12v wire to the coil (pink, if I recall correctly)

Terminal 86 (the control feed) is fed by the red/black wire from the ignition switch which has been disconnected from the fuseblock (see above). However, I see that this red/black wire has a back-feed from the alternator blue/black wire splice…

Terminal 85 is the earth wire to a convenient bolt on the dash underside (there is no earth-terminal rosette on this side of the car)

The engine started very well and idled for 10 minutes. At this point I thought I’d switch off and turned the key off. ………Engine continued to run with key OFF!

The easy way to stop the car was to take the main coil +12v feed from the coil.

I took the 5 pin ignition relay, which I had fitted, out of its holder and tested the female sockets:

12v is present at the high current feed with the ignition OFF as I expected, because it is straight off the battery +12v bus bar in the fusebox.

However still with the ignition OFF there was 0.6v at the low current control feed from the ignition switch; I was expecting 0v. I am wondering if that small voltage, indicating an unexpected current, is sufficient (when the engine is running and at a higher voltage from the alternator) to stop the relay unlatching and thereby allowing the current to the coil so that the engine carries on. The relay tests ok on the bench.

Looking at the ignition switch, the pigtails directly out of the switch ARE separate (there is no red/black wire there) but then those short pigtails go to a connector. At that connector (ie on the fusebox side of it), the blue/black wire to the ignition light and the red/black wire to the fuse block are connected. Hence there is effectively a feed from the alternator down the red/black wire (which I am using as the control wire for the relay) which I believe is causing the relay not to de-latch. The de-latch or drop out voltage of the relay was 2.7v on the bench (another one I tried was 3.9v) however.

I looked at the wiring diagram later and it seems that the control feed from the ignition switch is indeed spliced into the alternator-to-ignition light wire (blue/black at the ignition switch connector). So, I surmise that even though the ignition switch is turned off, whilst the engine “runs on”, the alternator is still pushing a voltage of at least 2.7v in the opposite direction.. As I say, that residual voltage seems to be enough to stop the de-latching or “dropping out” and the engine continues to run.

I wondered about fitting a diode enabled relay ie with the diode in the opposite direction to the alternator’s current BUT then surely I lose the ignition light? Which I do not want to do.

I want to keep the ignition relay add-on circuit within the fusebox and not run wires to the switch or take the switch apart again and separate terminals where etc.

Can anyone please explain what they used for a control feed for the ignition relay that does not allow the engine to “run on” but does keep the functionality of the ignition light and is a simple install. In other words how did you set up the ignition relay?

Thanks in advance.

RDS

 

[ng_randolph]

As you have found, there is enough current back-feeding from the alternator (through the warning light in the dash) to keep the relay energized.

It is tempting to do the wiring the way you did, because all the wires you need access to are right there, but it does not quite work without tweaks. A diode inserted in the thin BLU/BLK wire (anode towards ignition switch, cathode towards alternator warning light) will work, and you will retain use of the alternator warning light. But there is a simpler way: You can make a simple change at the ignition switch connector. Unpair the thin BLU/BLK wire from the 2.5 mm² RED/BLK wire and pair the BLU/BLK instead with the BLK and the BRN wires from the loom-side 4 pin connector for the ignition switch. RED/BLK does the exact same thing as the BLK and the BRN wires; hot in start and run. They just use separate contact pairs in the ignition switch. Wire colors as used in late model Bertone cars.

I have done something similar to what you are doing. I originally used a no-name 40A relay, and it gave out after about 10 years. At that point I replaced it with a 70A Panasonic branded automotive relay, part number CB1AH-M-12V. This relay uses 9.5 mm spades for terminals 30 and 87 (not the normal 6.3 mm), so new female contacts needed for the wiring.

 

[RDS]

Thanks Bjorn; I knew I would not have been the first!!

I note your "easier" modification at the 4 pin connector but so that I do not misinterpret, are you saying:
1 unpair the blu/blk wire from the red/blk wire at the loom side of the connector
2 pair the same blu/blk wire - I am sure you mean this wire - (or do you mean the red/blk wire - the word "it" can possibly be construed both ways here) to the "already twinned" BLK and BRN wires in the connector and not to the single BRN wire.
I ask because there are two brown wires in the connector; one in a single "way" and a pair of black and brown wires which are twinned in a single "way" in the connector you see.
Please rest assured I am not nit-picking but am very grateful; I only have one chance this weekend to get the car away from where it is you see!!

Thankfully I have not reassembled the steering cowl yet. from what you say, the diode protected relay suggestion will not work, because the diode is on the wrong leg of the unintended circuit?

ref the 9.5mm spades, I used them for the feed from the busbar; i looked for male counterparts (for another project) in that size and found none - are they not produced?

RDS

 

[ng_randolph]

1 unpair the blu/blk wire from the red/blk wire at the loom side of the connector

Yes.

2 pair the same blu/blk wire - I am sure you mean this wire - (or do you mean the red/blk wire - the word "it" can possibly be construed both ways here) to the "already twinned" BLK and BRN wires in the connector and not to the single BRN wire.
I ask because there are two brown wires in the connector; one in a single "way" and a pair of black and brown wires which are twinned in a single "way" in the connector you see.

The cavity that originally held one BLK and one BRN wire will now additionally hold the BLU/BLK wire liberated in step 1. The cavity with a single RED wire (for the starter) will remain untouched. The cavity with a single BRN (from the battery, via the bus box) will remain untouched.

ref the 9.5mm spades, I used them for the feed from the busbar; i looked for male counterparts (for another project) in that size and found none - are they not produced?

They are available, but not ubiquitous like the 6.3 mm type. TE part number 280074-2 is for AWG12 to AWG 10 wire (3.3 mm² to 5.3 mm²), and Farnell have 734 in stock at £0.208 ( ex VAT ) each. These are not insulated, so you would want a housing as well. And that could be a problem; TE has 2, 3 and 4 cavity housings for these, but not singles.

 

[RDS]

Thanks Bjorn - that is clear. Also thanks re the male 9.5mm spades. My search of CPC Farnell a few weeks back did not yield a result for insulated spades and I did wonder.

Turning back to your modification to the connector, following the instructions, you would have (leaving from the ignition switch) a blue/black pigtail going into the connector joining to the red/black wire and then also on the loom side the blue black wire being inserted into the black and brown cavity.

This colour mis-match might look a little confusing to a future owner: however I suppose that if instead of the suggestion above, I moved the red/black wire into the shared cavity of the black and brown wires in the connector, do you think that would cause issues with the lighting, because the brown and black wires go to the lighting switch? Looking at Haynes wiring diagram I do not think so, but I may be missing a consequence obvious to others.

Would either approach load the ignition switch contacts back up again, which I was trying to reduce by the use of the relay? I do not think so because the alternator current is still going through the same switch terminal as before and the ignition load is lessened by the relay arrangement anyway.
RDS

 

[lookforjoe]

Yes.

The cavity that originally held one BLK and one BRN wire will now additionally hold the BLU/BLK wire liberated in step 1. The cavity with a single RED wire (for the starter) will remain untouched. The cavity with a single BRN (from the battery, via the bus box) will remain untouched.

They are available, but not ubiquitous like the 6.3 mm type. TE part number 280074-2 is for AWG12 to AWG 10 wire (3.3 mm² to 5.3 mm²), and Farnell have 734 in stock at £0.208 ( ex VAT ) each. These are not insulated, so you would want a housing as well. And that could be a problem; TE has 2, 3 and 4 cavity housings for these, but not singles.

Newark.com has 280075 (Faston 375 series)

 

[RDS]

Thanks Hussein - I will order a few. Farnell' UK site was down 30 minutes ago when I tried to order!!

 

[RDS]

Still thinking about my query differing from Bjorn's instruction, one possible occurrence is that mine might cause the ignition light to remain lit at all times that the ignition is on which would not be a good result.

 

[ng_randolph]

Thanks Bjorn - that is clear. Also thanks re the male 9.5mm spades. My search of CPC Farnell a few weeks back did not yield a result for insulated spades and I did wonder.

Turning back to your modification to the connector, following the instructions, you would have (leaving from the ignition switch) a blue/black pigtail going into the connector joining to the red/black wire and then also on the loom side the blue black wire being inserted into the black and brown cavity.

This colour mis-match might look a little confusing to a future owner: however I suppose that if instead of the suggestion above, I moved the red/black wire into the shared cavity of the black and brown wires in the connector, do you think that would cause issues with the lighting, because the brown and black wires go to the lighting switch? Looking at Haynes wiring diagram I do not think so, but I may be missing a consequence obvious to others.

Would either approach load the ignition switch contacts back up again, which I was trying to reduce by the use of the relay? I do not think so because the alternator current is still going through the same switch terminal as before and the ignition load is lessened by the relay arrangement anyway.
RDS

The loom side connector has four cavities. If you do what I proposed, you will end up with cavities loaded as follows:

• Single BRN wire which is the battery feed. This must remain untouched.
• Single RED wire with go to the starter. This must remain untouched.
• Single RED/BLK wire with ignition switched power that you will use to trigger your relay.
• Bundle of BLK wire, BRN wire and BLU/BLK wire. This is for lighting and alternator lamp / alternator trigger.

You can swap the positions of the last two if you so desire. Lighting will be powered through the ignition switch, just as if you didn't do a swap, but now using the ignition switch contact set originally used for "all other loads". The rest of the ignition switched loads will be powered through your relay (bypassing the ignition switch as intended), but the relay will be triggered by the ignition switch contact set originally used for lighting. No harm in doing this if it satisfies your sense of order. The alternator light will work as intended either way.

 

[RDS]

Many thanks Bjorn; weather permitting I will see which of those two routes I will follow tomorrow and report back.

 

[kmead]

Thanks Bjorn - that is clear. Also thanks re the male 9.5mm spades. My search of CPC Farnell a few weeks back did not yield a result for insulated spades and I did wonder.

Turning back to your modification to the connector, following the instructions, you would have (leaving from the ignition switch) a blue/black pigtail going into the connector joining to the red/black wire and then also on the loom side the blue black wire being inserted into the black and brown cavity.

This colour mis-match might look a little confusing to a future owner: however I suppose that if instead of the suggestion above, I moved the red/black wire into the shared cavity of the black and brown wires in the connector, do you think that would cause issues with the lighting, because the brown and black wires go to the lighting switch? Looking at Haynes wiring diagram I do not think so, but I may be missing a consequence obvious to others.

Would either approach load the ignition switch contacts back up again, which I was trying to reduce by the use of the relay? I do not think so because the alternator current is still going through the same switch terminal as before and the ignition load is lessened by the relay arrangement anyway.
RDS

I would respectfully suggest making a wiring diagram reflecting the ultimate changes you have made to the wiring both for yourself (in a few years you will have little recall of what you did) and for the future owner.

An alternative following your approach would be to move the alternator light feed over to the output from the relay at the fuse box which would provide power more directly related to what the battery is seeing as a load and less affected by the vagaries of an old switch’s contacts.

An alternative approach would be to put the relays between the existing ignition switch connector and the loom connector which could be a removable plug and play solution. This would use three relays controlled by the ignition switch. One for the starter which will be best located in the spare tire well or a waterproof relay in the engine bay. Two relays to deal with the actual loads of the car. These relays likely don’t need to be rated for such a high load presuming you are also using headlight and wiper relays to improve the power delivery to those components down stream.

You would ideally need the plastic connectors to mate to the existing ignition switch and the loom side connectors.

So following Bjorn’s listing:

The loom side connector has four cavities. You will end up with cavities loaded as follows:

• Single BRN wire which is the battery feed to the ignition switch. This would remain untouched as it is the power delivery to the ign sw.
• Single RED wire goes to the starter. This would remain untouched, but is now a low voltage trigger wire to a remote relay from the ignition switch.
• Bundle of RED/BLK wire and the BLU/BLK wire untouched which will be fed from the second relay’s output
• Bundle of BLK wire, BRN wires untouched, fed from the third relay’s output.

I put the relays behind the glovebox (non AC car), right above the fuse box with a power buss bar from the battery alongside to feed directly from the battery. One could adjust the loom so the connector is near the relays, thus shortening the wires to the fuse box and related relays being fed.

I would suggest using known, quality name brand relays and properly gauged wire for these sorts of mods to ensure reliability and safety.

I have also included Rachaeljf’s PDFs for another approach to resolving some of this.

 

[RDS]

Thanks Karl; I am interested in all alternatives to the problem. For those who want to know, the use of a diode enabled relay did not allow the engine to stop with the key.

Yes I have been keeping notes of all the work and wire colours used, intending from the outset to annotate the wiring diagrams; actually I have to do two sets - one for the home based manual and one for the car's copy.

Re your alternative 1, I think that would mean extending the blue/black wire from the connector at the ignition switch over the centre of the car to the fuse box, yes?

Re alternative 2, I believe that will require an amount of space under the dash that I simply do not have - the Panda switch 4-relay bank takes up the only space available (the second channel speaker hogs the rest). I would also need the same factory connector to plug and play; i bet it is not standard and that I would have to fit a new matching male and female set. I say this because it took me a very long time to get two terminals out of that loom connector today and even longer to get them back in! There was no slack at all in the loom side of the wiring to allow good access to the connector.

In the end, so as to achieve my variation on Bjorn's suggestion above, I had to solder an extension red/black wire to the twinned black/brown terminal on the loom side, which I had just about managed to liberate from the connector, and solder the other end (covered with heatshrink) to the red/black wire, which I had cut away from the blue/black wire within the connector. This was fiddly in the extreme and if this was the "easier" method, I would hate to try to undertake the medium method.......!!

I finally put the connectors back together and started the car (ignition light visible before key going over to START); ignition light was off in RUN and the engine did shut off when the key was returned to OFF. I followed up by a good drive tonight.

I stress that I tried to over-spec the gauge of wires on this project and the lessons learned include using proper crimpers and good quality relays - I had several cheap ones fail quickly or arrive dead. I checked the resistance of the relay coil: 60Ohm which means the extra load on the blue/black wire terminal at the ignition switch is 0.2A, not a massive amount to make me worried about overloading the switch again.

Thanks also for the articles by Rachael. I am very tempted to fit the starter relay although I do not think the wiring follows the route in the diagrams in my car so that access will be a little harder but still achievable; I have the fuel pump relay in the spare tire area also. As for the dipped beam relay mod I fitted twin relay banks in each pod hatch with independent heavy gauge cable direct from the battery. Now however, I have lost the dim-dip function that I had before!! I will post that on the headlamp pod thread I started for completeness but the issue is as follows.

I would like the dim-dip function back - there is now no difference in light between dim-dip and dipped beam, except that the charging voltage with the engine running is 12.2v with the light switch in position 2 and 11.8v in position 3 - these look very low to me. Switching the lights off and the charging voltage shoots up to 17v!! This looks very high to me. Thinking aloud about this, I wonder if this has anything to do with my separating the alternator and coil wires at the ignition switch?

I appreciate the assistance from all, on this problem.

RDS

 

[lookforjoe]

Depending on what H/L bulbs you are using, the current draw may be very high - that's the only explanation I can see for the massive over-compensation when they are turned off - although 17V can't be good for any part of your wiring/components. Are you sure your meter is accurate? You may have a defective voltage regulator if it is.

No suggestions on the H/L pod issue - I don't have those to worry about anymore.

 

[ng_randolph]

I would like the dim-dip function back - there is now no difference in light between dim-dip and dipped beam, except that the charging voltage with the engine running is 12.2v with the light switch in position 2 and 11.8v in position 3 - these look very low to me. Switching the lights off and the charging voltage shoots up to 17v!! This looks very high to me. Thinking aloud about this, I wonder if this has anything to do with my separating the alternator and coil wires at the ignition switch?

I believe the dim-dip setup was for the UK only, and I have not seen the wiring diagram for it as it applies to the X1//9.

As for seeing 17V with headlights off - that is a real problem and I would not drive the car until it is sorted out. It is not related to your "separating the alternator and coil wires at the ignition switch" The coil and ignition system is not part of the charging system, and is related to the alternator only insofar as the alternator is what supplies power to the ignition system (and all other loads in the car) when the engine is running. The BLU/BLK wire (for the alternator warning light) that you relocated is not to blame either. Any problems here may prevent the alternator from charging at all, but will not cause an over-voltage situation.

As Hussein (@lookforjoe) suggested above, you probably have a failed voltage regulator on the alternator. If it were my car, I would simply replace the voltage regulator without doing any further testing. This is assuming you have the stock alternator; it is a different story if you have retrofitted a non-stock alternator with remote voltage sense.

 

[RDS]

Depending on what H/L bulbs you are using, the current draw may be very high - that's the only explanation I can see for the massive over-compensation when they are turned off - although 17V can't be good for any part of your wiring/components. Are you sure your meter is accurate? You may have a defective voltage regulator if it is.

No suggestions on the H/L pod issue - I don't have those to worry about anymore.

Hello Hussein

yes I see that you have dispensed with the troublesome items.......

bulbs are standard H4 nothing "special". I thought the same as you, overnight, the meter is the old one that I leave in the car to the vagaries of damp and cold so I will test it again today because it indeed may be faulty.

Also I will "jump" the alternator wire connection back to "factory" to see if anything changes. Apart from that, yes, i also consider the regulator with some suspicion at this moment.

 

[RDS]

thanks Bjorn; I will test the meter first: it is the one I keep in the boot and is definitely "third division" standard. I did suspect the regulator a while back. Yes the alternator is standard; I'll see what regulators are easily available here.

The Dim-dip worked with the relay bank loosely connected in the car two weeks or so ago but not now the bank has been secured under the dash - with no miles driven either! Another mystery.

RDS

 

[lookforjoe]

thanks Bjorn; I will test the meter first: it is the one I keep in the boot and is definitely "third division" standard. I did suspect the regulator a while back. Yes the alternator is standard; I'll see what regulators are easily available here.

The Dim-dip worked with the relay bank loosely connected in the car two weeks or so ago but not now the bank has been secured under the dash - with no miles driven either! Another mystery.

RDS

I would make the regulator #1 priority. 17V will kill many things - circuit boards, relay coils, etc., are not designed for that.

On an '87, the V/reg should be internal to the alternator - mounted in the back under the protective heat shield/air duct. It's only held in with two machine screws. Hopefully yours has a Bosch alternator, in which case the regulator is ubiquitous to (European) cars of that generation, and can be found very cheaply (for aftermarket, non Bosch) from many sources.

It would look like this (Volvo listing)

 

[RDS]

Cheers Hussein, I will get a reg anyway.

Just been out testing - panic over? maybe, maybe not; see below. Comments welcome (apart from get an expensive VM!). ID of the VMs was only for me to get the readings quickly into a table. The UNI-T was once supposed to be a good meter, which I abused and which I used last night and saw 17v in the dark. Is it possible that the Reg will work well and then play up? Surely they work, work over or work under or go open circuit?
Given the results, I decided not to "jump" the blue/black to the now tripled black, brown and red/black wires at the ignition switch connector.
I am tempted to road test again later unless this still gives cause for concern?

Fiat x1/9 voltages
29/08/2021​
No discernable difference in light intensity between Pos 2 and Pos 3 dipped beam, ie dim-dip not working
		Volt Meter			suspect item
RPM	Light Switch Position	Cigar plug in	yellow/blue	yellow black	Black UNI-T
0 START	Pos 1	12.02​	12.6​	12.85​	12.3​
2000​	Pos 1	12.9​	13.13​	13.46​	12.9​
2000​	Pos 2	12.1​	12.31​	12.62​	12.1​
2000​	Pos 3 dip	12​	12.3​	12.63​	12.1​
2000​	Pos 3 main	12​	12.27​	12.6​	12.05​
1000​	Pos 1	13.2​	13.24​	13.56​	13​
1000​	Pos 2	12.6​	12.5 dropping	12.56​	12.03​
1000​	Pos 3 dip	12.1​	12.25​	12.55​	12​
1000​	Pos 3 main	12.1​	12.2​	12.49​	11.95​
test took 10 mins
0 SHUT OFF	Pos 1	12.5​	12.58​	12.87​	12.35​
All readings except cigar plug in, taken at battery
Suspect unit and cheap cigar plug in very similar
No idea why one unit continually dropping volts
No repeat of 17v seen last night after run

 

[kmead]

Your alternator should be putting out @14.2 at the battery unless everything is on, even then it should be able to deliver 13.8v. I suspect either your regulator is on its way out (which if it is the Bosch unit will also replace the brushes) or time for a general rebuild.

To follow my suggestions yes you would need to acquire the standard connectors. MWB offers these used which is nice. You can also get them new as they are not specific to the car. Hussien I am sure has the part number at his fingertips (or on a yellow pad )

Yes, pulling the end of the alternator exciter wire over to the relay output could be either an extension or open the loom up and pull it back and trim it to go to the relay output.

 

[RDS]

Your alternator should be putting out @14.2 at the battery unless everything is on, even then it should be able to deliver 13.8v. I suspect either your regulator is on its way out (which if it is the Bosch unit will also replace the brushes) or time for a general rebuild.

To follow my suggestions yes you would need to acquire the standard connectors. MWB offers these used which is nice. You can also get them new as they are not specific to the car. Hussien I am sure has the part number at his fingertips (or on a yellow pad )

Yes, pulling the end of the alternator exciter wire over to the relay output could be either an extension or open the loom up and pull it back and trim it to go to the relay output.

Hello Karl

I will order the regulator to be on the safe side, however although that is the voltage that the text books say the charge should be, but I have never seen that on any car, classic or brand new modern, new battery or old!!

If Hussein has the connector part no, that would be good, perhaps I can source locally.
Extension to the blue/black exciter wire would be easier: there is no give whatsoever in the loom, it is probably looped over something.