88 Turbo S electrical issues

[Tom]

Sorry if that wasn't clear. I set the input voltage to 13.8. With a clean ground to the cluster Pin 8, and 13.8 volts to Pin 5, the gauge reads 13.8 volts, as it should. If I then insert a 30 ohm resistor in between the 13.8 voltage supply and Pin 5, the gauge reads about 12 volts. If I insert a 100 ohm resistor in between the 13.8 voltage supply and Pin 5, the gauge reads below 10 volts.

[Darwin]

Ok, so resistance absolutely plays a factor. I’m beginning to think I may have induced this issue when I replaced the battery cables. I’m going to remove and clean all of the 12v accessory leads on the positive battery terminal and see if I’m that improves anything.

[Tom]

Worth a shot, I'm just unclear why you are seeing a 12 volt reading on the gauge if there's really 138 ohms of resistance between your battery and pin 5. At least on my best test, 138 ohms basically prevents the gauge from registering any voltage at all....

[Darwin]

Just in case anyone else is messing with their cluster, be sure to be careful if you have power on…don’t touch the diode contacts to anything metal like the dash frame…

11258FEB-F81F-4D12-8B85-E8E46E0A169A.jpeg (3.22 MiB) Viewed 943 times

[Tom]

Sorry about that. I'd probably just solder a regular old wire from the diode's lead crimp to the crimp it went to, but the also make various conductive paints you can use for a tidier repair.

https://www.adafruit.com/product/1306?g ... gKLJfD_BwE

https://www.amazon.com/CircuitWriter-Co ... 2778&psc=1

https://www.amazon.com/MG-Chemicals-Car ... 5631&psc=1

[Darwin]

I have a spare cluster, so last night I swapped the membranes. Every single number on them are the same, and PET only shows a single part number for the membrane itself so I’m thinking it will be good. I’ll know this afternoon when I get home and can try it out!

[gruhsy]

Hey Darwin.

I can repair that trace at my work if you want.

Just in case anyone else is messing with their cluster, be sure to be careful if you have power on…don’t touch the diode contacts to anything metal like the dash frame…

11258FEB-F81F-4D12-8B85-E8E46E0A169A.jpeg

[Darwin]

Hey Darwin.

I can repair that trace at my work if you want.

Just in case anyone else is messing with their cluster, be sure to be careful if you have power on…don’t touch the diode contacts to anything metal like the dash frame…

11258FEB-F81F-4D12-8B85-E8E46E0A169A.jpeg

That's super kind of you. For now, the spare membrane appears to be working well. If I have issues with it, I may hit you up for that help!

[Tom]

Hey Darwin.

I can repair that trace at my work if you want.

Just in case anyone else is messing with their cluster, be sure to be careful if you have power on…don’t touch the diode contacts to anything metal like the dash frame…

11258FEB-F81F-4D12-8B85-E8E46E0A169A.jpeg

What process would you use? Just curious what options exist for something like that?

[Tom]

Hey Darwin.

I can repair that trace at my work if you want.

Just in case anyone else is messing with their cluster, be sure to be careful if you have power on…don’t touch the diode contacts to anything metal like the dash frame…

11258FEB-F81F-4D12-8B85-E8E46E0A169A.jpeg

That's super kind of you. For now, the spare membrane appears to be working well. If I have issues with it, I may hit you up for that help!

So the dedicated grounds did fix it?