94 940 no brake lights or c/c????

gsxrcirk · Post by **gsxrcirk** » 27 Sep 2007, 15:26

My 94 940 doesnt have brake lights or c/c for whatever reason? The fuses all check out good at least the ones inside the car. The only thing that had been done recently was that I tried installing new rear speakers. Im not sure if I did something wrong or not. The speakers are currently disconected. Does anyone have any ideas? Im mechanical but not real elecrical savey. Thx

Post by **billofdurham** » 27 Sep 2007, 15:59

Usually when all brake lights go out and the fuse is OK the next thing to check is the brake light switch which is mounted above the brake pedal.

With cruise control there is a link from the brake light switch to the C/C module. Looking at a wiring diagram it would appear that if there is no power coming through that link the C/C will not work.

Bill.

Z Volvo · Post by **Z Volvo** » 28 Sep 2007, 10:10

If you checked everything that Bill had mentioned fuses, switches etc..it is the Bulb failure sense relay, round red relay in upper left side above fuse box. Pain to get to if you have clubs instead of fingers like I do. You will need to remove the ashtray and storage box/cigar lighter assembly above the fuse access.(Center of dash below radio)there is an illustration in the owners manual of which relay does what. cigar lighter cover just lifts off and two screws hold it in.Carefully angle it out and you should see the relay at the back of the compartment left side.I had same issue last week, after I had replaced ignition coil, wires plugs etc..and removing center brake light to clean glass, should not have caused a problem but who knows which automotive gremlin I irritated recently. Anyway got part online for 48 dollars and even with over night shipping came out 30 dollars less than most stores or other online options. I will send you the name in a private message. this week check engine light came on after oil cooler hose sprung a leak around the oil filter. ordering hoses and stuff on line just trying to decide if I should go with just the oxygen sensor and do the wiring (40 to 60 bucks) or get with known harness(156 bucks). Seems the car is conspiring against me, I just put new Yokohamas on it and a new wheel(kids) I thought this would make her happy. Hope this helps you.

Note: Do not leave the wires from the speakers exposed and un-connected, this may cause a short and ruin all your good efforts, isolate with electrical tape or shrink tubing if you are not yet finished your upgrades.

Tom1993940turbowagon · Post by **Tom1993940turbowagon** » 07 Feb 2008, 05:56

I had a similar problem with my Volvo a few years ago. Although it did not affect my rear lights.

When I activated the turn indicator, the cruise control quit.

It turned out that after years of using the turn indicator, a wire from the turn indicator handle that went into the steering column that apparently connected to the brake switch got worn and finally separated.

If memory serves, the insulation on the wire was green, but I could be mistaken. If that is your problem, you should be able to see a cracked or obviously separated wire.

Volvo didn't allow enough slack in mine so the wire wore out and separated after several years of turns.

I had to add an extra length of wire to both ends and that fixed it.

Be extra careful when you strip the wire ends to add the extra length. There is almost no slack in the wire and you have to do it right the first time and avoid breaking off what little copper wiring you have to work with on the original wire.

I didn't proceed as carefully as I advise you and it took me a lot of delicate work to get the ends twisted together and insulated.