[ajb303]

Hi all -

I recently saved a 1971 145S. It's been a good project since shelter in place was issued. The wiring was a mess and I have started to go through it by taking out all aftermarket components and reseting it to the wiring diagram in my green book. I figured I would start this thread for my questions as they come.

(1) Tailgate wiring. I have successfully troubleshooted the license plate light (driver side), defrost (driver side), and rear wiper motor (passenger side) hot wires coming from each of their dash switches. There is still one more wire that is always hot when the key is in the on position, and it's coming from the passenger side in the same harness as the rear wiper motor. Does this also go to the rear wiper motor? Any idea?

(2) Headlight wiring. When my headlight dash switch is in the "half position" or "parking light position" my dipper lights are coming on. When the switch is in the "full position" the main beams are on. I am not able to switch between high and dipper from the steering column lever even the the wire does go to the correct relay position. The only wrong position on my headlight relay I believe is terminal 56a a yellow wire should go to the steering column, but it's actually going to the dash switch.

Thank you in advance for your help.

 

[142 Guy]

(1) Tailgate wiring. I have successfully troubleshooted the license plate light (driver side), defrost (driver side), and rear wiper motor (passenger side) hot wires coming from each of their dash switches. There is still one more wire that is always hot when the key is in the on position, and it's coming from the passenger side in the same harness as the rear wiper motor. Does this also go to the rear wiper motor? Any idea?

(2) Headlight wiring. When my headlight dash switch is in the "half position" or "parking light position" my dipper lights are coming on. When the switch is in the "full position" the main beams are on. I am not able to switch between high and dipper from the steering column lever even the the wire does go to the correct relay position. The only wrong position on my headlight relay I believe is terminal 56a a yellow wire should go to the steering column, but it's actually going to the dash switch.

1) What color is the wire? The rear wiper motor has two supply wires, grey to 31b and blue to 53a. It also looks like an external by-pass diode between 31b and 53 and a ground connection on what looks like 31. No other connections. There is a rear interior light. I can't remember whether its in the tailgate or the roof at the back. The supply wire is red; but, I thought it was always hot, not switched.

2) Things appear to be quite messed up. 56a should have a red wire and a W/R wire. The red wire is the supply to the headlight high beam filament and the W/R wire goes to the top of fuse #2. The other side of fuse #2 connects to the high beam indicator in the dash. No other connections on fuse #2 at all. The yel wire should be on terminal 56 of the relay and goes to terminal 56 of the headlight switch on the dash. Terminal 81 a on the relay should have a green wire which goes to terminal 88 on the headlight relay switch.

Are you trying to do this without a wiring diagram? If you still have the owner's manual, there is a tiny wiring diagram in the owner's manual. If not, a quick Google search using 'Volvo 145 wiring diagrams' should get you some hits. Trying to do this without a wiring diagram reminds me of the 'even a blind pig finds an acorn once in a while' idiom.

 

[Ron Kwas]

Ajb; (A name is not required, but would be nice!)

Welcome to this Forum!

142G has a very good start on your Qs...fact is that the wiring colors shown in the factory Wiring Diagrams are typically very consistent with whats in the cars, so you should always start with a WD in hand, and go by wire colors...

Regarding headlights...they are controlled by a bi-stable relay the position of which is itself under control of the momentary contact at the Stalk control...but there is also a momentary contact which is made (to power brights) only when Stalk control is activated...and you should hear the relay clacking each time you activate the Stalk control.

Further info on bi-stable relay here: https://www.sw-em.com/headlight_control_upgrade.htm

Good Hunting!