Brake lights won't work, fuses, switch good

Seake · Post by **Seake** » 30 Mar 2011, 17:46

2003 XC90 brake lights won't work but the third upper light does. The brake light switch appears to be working because I can shift out of park. All fuses are good and I installed new bulbs. Any suggestions?

Post by **jimmy57** » 30 Mar 2011, 18:13

Shunt or relay on the REM in the left rear quarter panel. Fuses should be checked too. Shunts are those black thin rectangular things plugged into the REM. If you download wiring diagram from the Repair Database tab, it will pinpoint which shunt on the brake lights pages.
Third brake lamp is not routed through REM, it feeds directly off the CEM.

Seake · Post by **Seake** » 30 Mar 2011, 19:32

Thanks Jimmy, I swapped out a relay from a component that was working and that solved the problem. The relay for the brake lights was a different color, I'm assuming it was replaced before. Wondering if there is something else going on that required that relay to be replaced now 2 times.

Shawn_Mtl · Post by **Shawn_Mtl** » 29 Apr 2011, 19:40

Wow, I just fixed the same problem today by switching out my relay. I guess I should have read the posts yesterday. My original relay was blue, the new part number is black like the others. Cheers

Chadbedford · Post by **Chadbedford** » 09 Jan 2013, 16:36

I checked all the fuses replaced the bulbs. Bought an additional rectangular fuse like you suggested still no brake lights. Any more suggestions

Post by **mrbrian200** » 16 Jul 2017, 17:35

Does anyone off hand know what the new part number is? '03 XC90

I'm wandering if the surgical operation I did on a 9441161 today (the common mini SPDT relay used all over on these and other P2s/P3s) was unnecessary and I could have just plugged the 9441161 in as is.

Fearing a warning message on the DIM or some weird brake light malfunction I extracted the diode out of the original blue relay and installed it across the leads of the new (technically used/low use relay from a pick and pull) . Also clipped the unused SPDT 'closed when off' spade terminal, again fearing the REM would see it and display some bitter message on the DIM about it.

9441161 same coil resistance, same current rating, both are built for SPDT internally, just the blue one has that spade lopped off just like I did to the 9441161. The only real difference is that small signal diode wired to shunt reverse current across the coil on the blue one. I am curious why they're worried about reverse current across the coil on this particular relay (but nowhere else/any of the other relays on the car that I can tell)

I needed the brake lights to work by tomorrow morning - not 2 or 3 days from now. Relay would have to be either ordered or drive to nearest Volvo dealer 80 miles away. And it's Sunday.

Post by **ALF1** » 08 Sep 2017, 17:18

I experienced the same symptoms. Replaced all rear light bulbs (brake, turn, running) and used the electrical grease on them. No more problems.