VAbeachFC

alright whats up everyone? heres the deal. 87 s4 se

got the tranny rebuilt back in oct 2007 ever since then i havnt had reverse lights. i personally dont care if i have reverse lights or not but virginia thinks its a good idea so we have state inspections here. the past 2 yrs ive just paid for the inspection sticker, well dude man cant supply the stickers anymore so now i have to fix this problem. so this morning i jack up the car and find wires cut out the driverside. ok those must be the reverse wires. the wires are red,red coming from top of tranny then i have a black/yellow and red/green wire coming from starter harness. so i spliced up a wire and hooked them up accordingly. test for reverse lights all goes well. i hop in the car to go get it inspected and bam no gauge readings at all and no reverse lights. meter fuse blew. went to replace with another 7.5 and bam blew again. i disconnected the wires i had connected and put another 7.5 fuse in and all my gauges work again. my question is where did i go wrong on this one? ps virginia sucks dont ever come visit us lol...

ifryrice

B/Y is the power source coming from the fuse. It goes into the reverse light switch, and comes out as R/G.

The colors should remain the same from the harness itself to the switch, it would appear your connector is likely missing all together. Find those 4 wires and connect them up and you should be fine.

Colors are for the following:
B & G/B - Neutral SW
B/Y & R/G - Reverse SW
B & B/L = 5th

RotorRex

iTrader: (2)

The two red ones from the switch are your backup/reverse switch. They'll have a 'bullet' type of connector on them. They go to the same type of connectors on the harness (B/Y & R/G).

My guess is that there's a short somewhere in either the backup light wiring or in the switch itself. probably why they were cut... prev owner couldn't find the short and cut/disconneted the wires. IMO

Try jumping the connection between the B/Y and R/G wires. This puts it in full time reverse (as far as your lights are concerned). If you still blow fuse, it's in the wiring (don't envy that search). If it only blows when hooked up to the tranny switch, then I'd go to Autozone and get another switch.

(LOL at the 'spinnin doritos')

ifryrice

Gotta love stuff not in the FSM, and no car to go check nearby. I wonder if he connected only one, or both, or connected them to another color.

RotorRex

iTrader: (2)

No ****. The FSM is pretty fuzzy on the backup lights diagram. Hailers and Aaron Cake helped me clarify a couple of things. I just ordered a new switch from O'Reilly's last week. should come in tomorrow. mine have been dead for a couple of years, but I never really cared much. got bored over the holidays and started tackling electrical gremlins in my SE.

The FSM wiring diagram makes it look like there are two seperate switches for reverse and 'over the top', but it's all in same part. The leads coming out of the switch are 2-red and 2-green. 2 red wires have the bullet connectors and are identical/interchangable. 2 green wires have one male and one female connector that match the female/male connectors on the harness.

My money is on bad switch. something probably is shorting across inside the little bastard.

ifryrice

What a fantastic choice of color wiring. Since R/G is used as one of the colors, i'm sure someone at some point spliced the R/G or B/Y wire in with one of those greens thinking they somehow went together, shift into 5th and she grounds and takes your fuse with it.

VAbeachFC

i never shifted into 5th i hooked those wires up everything worked started to drive the car and meter fuse blew then no reverse lights.

ifryrice

Probably a faulty switch, or somehow the wiring contacted ground.