Dr.Jeff
True Classic
I saw the following comment by @Bobkat in another thread, "I wired the Italian right out of it and did every mod possible." He was referring to doing some electrical mods to his X, which brought this subject to my mind. Over the years we've discussed lots of excellent ways to improve the X1/9's electrical system - BWM, relays, ground lugs, heavy gauge wires, etc. So throughout my file of X1/9 notes I have several write ups and diagrams saved. However I need to organize all of it and see what the final "to do list" will be for the whole electrical system.
Off the top of my head here is a list of the things that can be done to improve the X's electrical system. The idea here is not to explain how each mod is performed, but more a list of possible mods that one might consider doing to their X. I don't recall this already being done somewhere (in a single location), if so I apologize for the redundancy (and direct me to it). Otherwise please add to, subtract from, or alter this to see if we can make a comprehensive list of possible X electrical mods:
1) The "brown wire mod" (BWM). This term has been used to describe a few things. To me it is about adding a heavy gauge wire from the battery to the fuse box input, providing a greater load capacity for everything in the fuse box. I've seen some also refer to adding another heavy gauge wire from there to the ignition switch. However it seems to me that would only allow more current to pass through the switch, which is already very overloaded. I believe it is better to reduce the load through the ignition switch by adding relays for the big power consumer components elsewhere. With that there shouldn't be a need to replace the lead to the switch (more on this later).
Speaking of the BWM, I believe the stock power wire feeding the fuse box differs on various years of X? I've never owned a 1300 X so cannot say for sure, but I think it has one small lead going to the fuse box. My '79 (1500) splits into three leads to the box, and my '86 has a different arrangement yet again. Anyone have more details on what years had what wires powering the fuse box?
2) Closely related to #1 is changing the cables from the alternator to the starter motor, and from the starter motor to the battery, with much heavier ones. Although the battery might be considered the primary power source, the alternator provides the electrical supply to the battery - via the starter motor. The stock cable between the alternator and starter is very undersized. The stock cable from the starter to the battery is better but it is also a much longer run, so it needs to be heavier. Improving these cables will allow the full charge from the alternator to reach the battery.
3) Adding auxiliary relays to power large load components. This involves building supplemental wire harnesses from a main power source (battery or alternator) to each of the items that draw a lot of current, with a relay triggered by the original circuit to that item. On the stock wiring harness these items are powered with wires that are not heavy enough to allow full current. Furthermore the circuits are run through the ignition switch (as I commented earlier), overloading the switch and further reducing current. This reduction in current causes the components to run slow or improperly (if at all). Thinking of the components that might benefit from this, electrical motors draw a heavy load. Plus a few other items, it's a long list:
Starter motor solenoid trigger - 1 relay.
Wiper motor - 2 relays.
HVAC blower motor - 2 or 3 relays (depending if it is a 2 or 3 speed unit).
Radiator cooling fan(s) - 1 or 2 relays (1 for each fan).
Power windows (if equipped) -2 relays. Correction: 4 relays.
AC compressor clutch (if equipped) - 1 relay.
Headlights - 2 relays (low beam and high beam).
Headlight motors - 2 relays. [I've seen this mentioned but not sure if it helps over the stock relays].
?? what else, aftermarket sound system, additional driving lights, ??
That's a LOT of relays and extra wires. It should be noted that some components already have a relay in the stock wire harness/fuse box. But the gauge of the wires to/from those relays may not be sufficient. In these cases it isn't so much about adding the relay as it is changing the wires. But that isn't easy to do in the stock wire harness, so adding an auxiliary circuit with heavier wires and a new relay may be easier.
4) Improving ground connections. Every electrical component that has a power lead also has a ground lead, and both are equally important. So improving grounds will compliment the improved power supplies. Not to mention the stock grounding lugs tend to corrode. Cleaning and assuring that all of the "push-on" connectors are tight is a start. But I prefer to replace those "daisy" lugs and "push-on" connectors with a grounding bar and screw down connectors on each lead. Another good improvement is the ground straps between the battery and chassis, and the chassis and drivetrain. Same principle as we discussed with the power cables to the battery/alternator.
5) Repair and/or improve the electrical connector that goes to the ignition switch. This might sound a lot like the BWM but it isn't. The stock harness to the ignition switch has a 4-lead connector in a plastic housing, a few inches down from the switch. Due to the extremely high current loads placed on the ignition switch, this connection gets overloaded and melts the wires, connectors, and/or housing. Even if all of the other improvements are completed, a damaged connection here will still cause problems if not repaired.
6) Perhaps this should have been number one, but it really isn't a mod. Test and service the battery, alternator, and regulator to assure they are working correctly and in good shape. Some have improved the alternator by replacing it with a higher output unit. The GM alternator has been a popular mod for this.
7) The electrical load created by some components can be reduced by replacing the component itself with a lower current version. The most likely candidate here is light bulbs - especially the headlights. While adding relays to the headlights will improve the current supply to them, reducing the load with a different type of bulb is still a good idea (LED or HID have much lower loads). And those headlight relays will not have any effect on all of the other light bulbs on the car. They can be replaced with LED bulbs to significantly lower their demand. Furthermore, the improved lights (headlights and others) will significantly improve the illumination, making the car safer and more enjoyable.
Some other components that can be changed for a lower draw are a gear reduction starter, more efficient radiator cooling fans, others?
8) There are a couple of headlight related wiring mods that can be done to improve their functionality. They are separate unrelated items but close enough in nature - relative to the headlight switch operation. So I'll put both as one entry here on our master list: 1) The headlight door/pod function is a bit odd to accommodate a more European function, and US drivers may prefer to change how they behave - going up and down. For additional information see this thread [https://xwebforums.com/forum/index.php?threads/headlight-motor-rewiring.8237/]. 2) The function of the parking lights is also odd on some years of X. That can also be changed. See this thread for more [https://xwebforums.com/forum/index....-parking-light-operation-whats-correct.33293/].
?? what else can we add to this list? Please add comments so that I can organize my files and prepare for the mods to my X's.
As we see there is a LOT of "Italian" that can be removed from the X's electrical system. I once joked it might be easier to scrap the entire stock wire harness and install a aftermarket "universal" harness kit.
Off the top of my head here is a list of the things that can be done to improve the X's electrical system. The idea here is not to explain how each mod is performed, but more a list of possible mods that one might consider doing to their X. I don't recall this already being done somewhere (in a single location), if so I apologize for the redundancy (and direct me to it). Otherwise please add to, subtract from, or alter this to see if we can make a comprehensive list of possible X electrical mods:
1) The "brown wire mod" (BWM). This term has been used to describe a few things. To me it is about adding a heavy gauge wire from the battery to the fuse box input, providing a greater load capacity for everything in the fuse box. I've seen some also refer to adding another heavy gauge wire from there to the ignition switch. However it seems to me that would only allow more current to pass through the switch, which is already very overloaded. I believe it is better to reduce the load through the ignition switch by adding relays for the big power consumer components elsewhere. With that there shouldn't be a need to replace the lead to the switch (more on this later).
Speaking of the BWM, I believe the stock power wire feeding the fuse box differs on various years of X? I've never owned a 1300 X so cannot say for sure, but I think it has one small lead going to the fuse box. My '79 (1500) splits into three leads to the box, and my '86 has a different arrangement yet again. Anyone have more details on what years had what wires powering the fuse box?
2) Closely related to #1 is changing the cables from the alternator to the starter motor, and from the starter motor to the battery, with much heavier ones. Although the battery might be considered the primary power source, the alternator provides the electrical supply to the battery - via the starter motor. The stock cable between the alternator and starter is very undersized. The stock cable from the starter to the battery is better but it is also a much longer run, so it needs to be heavier. Improving these cables will allow the full charge from the alternator to reach the battery.
3) Adding auxiliary relays to power large load components. This involves building supplemental wire harnesses from a main power source (battery or alternator) to each of the items that draw a lot of current, with a relay triggered by the original circuit to that item. On the stock wiring harness these items are powered with wires that are not heavy enough to allow full current. Furthermore the circuits are run through the ignition switch (as I commented earlier), overloading the switch and further reducing current. This reduction in current causes the components to run slow or improperly (if at all). Thinking of the components that might benefit from this, electrical motors draw a heavy load. Plus a few other items, it's a long list:
Starter motor solenoid trigger - 1 relay.
Wiper motor - 2 relays.
HVAC blower motor - 2 or 3 relays (depending if it is a 2 or 3 speed unit).
Radiator cooling fan(s) - 1 or 2 relays (1 for each fan).
Power windows (if equipped) -
AC compressor clutch (if equipped) - 1 relay.
Headlights - 2 relays (low beam and high beam).
Headlight motors - 2 relays. [I've seen this mentioned but not sure if it helps over the stock relays].
?? what else, aftermarket sound system, additional driving lights, ??
That's a LOT of relays and extra wires. It should be noted that some components already have a relay in the stock wire harness/fuse box. But the gauge of the wires to/from those relays may not be sufficient. In these cases it isn't so much about adding the relay as it is changing the wires. But that isn't easy to do in the stock wire harness, so adding an auxiliary circuit with heavier wires and a new relay may be easier.
4) Improving ground connections. Every electrical component that has a power lead also has a ground lead, and both are equally important. So improving grounds will compliment the improved power supplies. Not to mention the stock grounding lugs tend to corrode. Cleaning and assuring that all of the "push-on" connectors are tight is a start. But I prefer to replace those "daisy" lugs and "push-on" connectors with a grounding bar and screw down connectors on each lead. Another good improvement is the ground straps between the battery and chassis, and the chassis and drivetrain. Same principle as we discussed with the power cables to the battery/alternator.
5) Repair and/or improve the electrical connector that goes to the ignition switch. This might sound a lot like the BWM but it isn't. The stock harness to the ignition switch has a 4-lead connector in a plastic housing, a few inches down from the switch. Due to the extremely high current loads placed on the ignition switch, this connection gets overloaded and melts the wires, connectors, and/or housing. Even if all of the other improvements are completed, a damaged connection here will still cause problems if not repaired.
6) Perhaps this should have been number one, but it really isn't a mod. Test and service the battery, alternator, and regulator to assure they are working correctly and in good shape. Some have improved the alternator by replacing it with a higher output unit. The GM alternator has been a popular mod for this.
7) The electrical load created by some components can be reduced by replacing the component itself with a lower current version. The most likely candidate here is light bulbs - especially the headlights. While adding relays to the headlights will improve the current supply to them, reducing the load with a different type of bulb is still a good idea (LED or HID have much lower loads). And those headlight relays will not have any effect on all of the other light bulbs on the car. They can be replaced with LED bulbs to significantly lower their demand. Furthermore, the improved lights (headlights and others) will significantly improve the illumination, making the car safer and more enjoyable.
Some other components that can be changed for a lower draw are a gear reduction starter, more efficient radiator cooling fans, others?
8) There are a couple of headlight related wiring mods that can be done to improve their functionality. They are separate unrelated items but close enough in nature - relative to the headlight switch operation. So I'll put both as one entry here on our master list: 1) The headlight door/pod function is a bit odd to accommodate a more European function, and US drivers may prefer to change how they behave - going up and down. For additional information see this thread [https://xwebforums.com/forum/index.php?threads/headlight-motor-rewiring.8237/]. 2) The function of the parking lights is also odd on some years of X. That can also be changed. See this thread for more [https://xwebforums.com/forum/index....-parking-light-operation-whats-correct.33293/].
?? what else can we add to this list? Please add comments so that I can organize my files and prepare for the mods to my X's.
As we see there is a LOT of "Italian" that can be removed from the X's electrical system. I once joked it might be easier to scrap the entire stock wire harness and install a aftermarket "universal" harness kit.
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