86 Chevy S-10
Question:
break it into halves in this case, the best point is the switch check for voltage on one terminal of the switch in neutral, and on both in reverse there will be three posibilities: 1) voltage on one in neutral, on both in reverse = OK 2) voltage on one in neutral, on the same one ONLY in reverse = bad switch 3) voltage on none = no power to circuit if # 1, the fault is further along toward the tail end of the truck if # 3, the fault is back toward the fuse block hope this helps; test it and get back here with what you find and we’ll go
– Hide quoted text — Show quoted text -> Does anyone have any ideas what I should check for fuses, wiring, or > whatever for the cause of back-up lights not working. I have replaced the > switch on the transmission and they still don’t work. I’ve tried tracing > the wiring under the dash but have gotten nowhere. I really don’t want to > rip the dash out. Could I have missed a fuse? Anything under the hood I > should check? Help!!
Response:
Does anyone have any ideas what I should check for fuses, wiring, or whatever for the cause of back-up lights not working. I have replaced the switch on the transmission and they still don’t work. I’ve tried tracing the wiring under the dash but have gotten nowhere. I really don’t want to rip the dash out. Could I have missed a fuse? Anything under the hood I should check? Help!!
Response:
> Does anyone have any ideas what I should check for fuses, wiring, or > whatever for the cause of back-up lights not working. I have replaced the > switch on the transmission and they still don’t work. I’ve tried tracing > the wiring under the dash but have gotten nowhere. I really don’t want to > rip the dash out. Could I have missed a fuse? Anything under the hood I > should check? Help!!
Manual or automatic transmission? If AT, check for a park/neutral safety switch located on the bottom portion of the steering column. I am unsure which year GM started using this type of switch but IIRC it was 85′ so yours might have one. This switch is connected to the column shift mechanism and prevents start-up while in any gear other than park or reverse. In some years and models, this switch also powers the reverse lights as the circuit is completed when the shifter is in the "R" position. IIRC, the switch-to-reverse lights wire is a light green w/blue stripe. Check this wire for a 12V signal when the key is on and shifter in reverse position. Of course, if you have a manual transmission, ignore the above! Also, I assume you’ve checked/replaced the reverse light bulbs? — Take er’ easy, "Doc" Wrenchin’ since 1992 1988 GMC Sierra SLX aka "Chelsea" 1998 GMC Sonoma SLS aka "Ruby"
