Bulb position failure

Arnexas · Post by **Arnexas** » 28 Nov 2019, 13:07

So few weeks ago, my Volvo S80, 2001 computer screen (DIM) started acting strangely. If I'm driving, orange triangle starts turning on / turning off randomly together with the computer screen. Also, if I press brakes, "check stop lamp" comes onto the screen. All the bulbs work. I have connected VIDA, no faults found. After some looking, found out that REM module has these values:

1. Bulb failure, group 1 is flactuating between 0.7 Ampers and 0.1 Ampers when I press the gas pedal. Without pressing the gas pedal, it's flactuating between 0.7 - 0.6 Ampers. Actually it explains random flashing screen and orange triangle as the moment ampers go down below set treshold, the orange triangle pops up, but it immediately turns off as the ampers flactuating and not sitting below the treshold to show the message.
2. If I press brake pedal, the value for stop lamp immediately goes from 0 Ampers (this value is correct because brake lights are not activated) to ~5 Ampers (brake lights activated) and then instantly to around 3.6 Ampers. If I press gas pedal, it can go below 2 Ampers from 3.6 Ampers. If this value is less than 3 Ampers, I get the message to check the stop lamps. It is worse when driving and coming to the stop.

So it looks an easy fix - probably electrical contact problem. Checked all lamps, sanded bulb sockets and it looked like it helped at first. Next day the message and random flashing came back. Then I tried to change all the bulbs including number plate bulbs, but the message is still here. The bulbs are correct wattage, as specified in owners manual. Then, I tried to look at relay box - RMA5 and RSH6 which turned out fine - still getting error after changing them. What I found interesting, that if I try to wiggle either RMA5 or RSH6 relays, the error message is popping up / dissappearing randomly.

What can be wrong here? I'm thinking this can be REM fault. Probably trying to clean REM slots in the next days.

Post by **yagger** » 28 Nov 2019, 13:46

Check first ground connections under rear plastic cover.

Arnexas · Post by **Arnexas** » 29 Nov 2019, 03:33

Thanks for reply. I have checked both of the grounds, they are fine.

Post by **yagger** » 29 Nov 2019, 19:14

Also, you have to check water damages on all metal ways inside rear lamps. Sometimes there are gaps.

Arnexas · Post by **Arnexas** » 30 Nov 2019, 03:50

yagger wrote: ↑29 Nov 2019, 19:14 Also, you have to check water damages on all metal ways inside rear lamps. Sometimes there are gaps.

I have checked it. No water damage. I sanded all contacts once more. Now VIDA DICE shows that "REM-Bulb fialure, stop light" jumps to ~4.5 A instead of 5 A as before. Also, it flactuates at 4 A - 3.8 A (previously the maximum was 3.8 A) at idle, but if I press the gas pedal, it can drop to 3.6 A. The problem is that as while I was looking at VIDA DICE results, it started dropping to 3.2 A. I think that after some driving it will drop below 3 A again, as the problem is still here.

Also, "REM-Bulb failure group 1" is still a problem. As I sanded the contacts, it was 0.82 A, but as I was checking the stop lamp, it started flactuating between 0.82 A and 0.71 A. As soon as I press gas pedal - it drops down and the orange triangle / computer screen starts to flash. Also, I found out why I can't get message for this particular error - I found an activation in VIDA DICE to turn on error message for failed parking bulbs - the screen says I have an error, but it won't show it.

Post by **yagger** » 30 Nov 2019, 11:54

One more point. There are shunts on the REM. Like additional option, you can turn REM and check contacts to that shunts. Sometimes one from them can be burned.

Arnexas · Post by **Arnexas** » 01 Dec 2019, 04:41

yagger wrote: ↑30 Nov 2019, 11:54 One more point. There are shunts on the REM. Like additional option, you can turn REM and check contacts to that shunts. Sometimes one from them can be burned.

Checked it - contacts seems ok. I have found something strange:

If I turn on high beams - stop lamp amperage flactuates between 3.4 A - 3.8 A. As soon as I turn high beams off - it then flactuates between ~2.4 A - 3.8 A or even lower.
If I try to lift all the windows at once from drivers door module - stop lamp amperage flactuates between 3.6 A - 3.8 A and as soon as I stop lifting windows up - starts flactuating lower than 3 A again.

All these flactuatings starts when I press gas pedal. Without pressing it, flactuating is not that big. Also, I should mention that the flactuating gradually increases as I'm doing these "tests". Just after starting the car, pressing brake and gas pedals, stop lamp amperage shows 3.6 A - 3.8 A, but after like 3 minutes or so, it would go lower than 3 A every time I press the gas pedal.

Also, drivers window is not working, but it didn't work for quite some time, so that shouldn't be the cause of this problem.

Arnexas · Post by **Arnexas** » 01 Dec 2019, 05:36

After test driving, now it shows an error for rear fog bulb too even though it is working. If I try to lift all windows up - error for parking lights disappear, but stop lamp and rear fog lamp error still persists.

PainterPaul · Post by **PainterPaul** » 07 Jun 2020, 19:05

Did you ever get this problem resolved ?

Arnexas · Post by **Arnexas** » 08 Jun 2020, 00:54

PainterPaul wrote: ↑07 Jun 2020, 19:05 Did you ever get this problem resolved ?

No. Actually the message did dissapear for few months. It reappeared after cleaning the car interior - could be something moisture related.