1996 850 turbo - dash indicator lights stuck on

caymran · Post by **caymran** » 18 Aug 2012, 16:59

Hey guys, I have a problem with my 1996 850 turbo's dash indicator lights staying on with the key out.

So far I have replaced the ignition switch (no difference), removed all three overload relays (no difference), disconnected the alternator (no difference), removed the ignition switch (no difference), checked that when the ignition switch is removed x = 12v, 30 = gnd, s = gnd. Both the new switch and the old switch test fine from the diagrams I have.

I don't think it is the ignition switch or the relays. The immobilizer is not triggered (I did the door key thing anyway) and the radio code has been entered. Everything on the car works fine, starts, runs, a/c, radio, locks...

The only way I can get all of the indicator lights to turn out is to disconnect the battery entirely. Any idea where the problem could be or what I may have overlooked?

Thanks guys,
Caymran

Post by **rspi** » 18 Aug 2012, 17:06

What light(s) are you talking about? The lights that help you see the instruments at night?

caymran · Post by **caymran** » 18 Aug 2012, 17:18

No, all the indicators, abs, oil, temp, battery, all across the bottom of the dash... that would normally come on to alert you of a problem with some system. Or that would light up for a few seconds when you put the key in and turn to position II or start, then turn off after a few seconds if the systems are ok. My problem is they just stay on, key in or out.

Post by **Ozark Lee** » 18 Aug 2012, 21:00

More than likely it is a failing electrical portion of the ignition switch. It is a relatively cheap part and a very easy fix. We have a couple of writeups in the repair database.

...Lee

caymran · Post by **caymran** » 18 Aug 2012, 21:33

I have replaced the electrical portion of the ignition switch with a brand new one. Did not fix the problem. The warning indicator lights stay on even with the electrical portion of the ignition switch completely removed.

Post by **BEJinFbk** » 18 Aug 2012, 22:44

There have been more and more reports of clusters failing.
In a hopeful attempt to keep any harness issues out of this
scenario, you might try laying your hands on a known good
cluster and seeing what happens if you swap it out.

Post by **rspi** » 19 Aug 2012, 08:32

I just replaced a cluster. Sad part about it is that Volvo no longer sells it as an assembly, just parts. The circuit board alone is over $500.

I would hook up a OBD-2 tool and check to see if the alternator is charging the battery at 12.8+ volts. The car may interpret a disconnected alternator as a bad one.

caymran · Post by **caymran** » 19 Aug 2012, 15:14

Pulled the alternator entirely, had it tested at the local parts shop, it passed all tests. Pulled the cluster, took a look at the board, saw no obvious issues, went ahead and reflowed the solder on all chips and terminal connections, put back together and still the same issue. I am going to put a charger on it and make sure the battery is topped off (it had been parked awhile with the battery disconnected while I was waiting for time to fix it).

Does anyone have a good circuit diagram for the connectors on the cluster? I want to make sure I don't have a floating gnd at the cluster and also that lines that should be without +12v when the car is off don't have +12v.

Post by **BEJinFbk** » 19 Aug 2012, 15:23

All right here onsite:
https://www.matthewsvolvosite.com/volvo-wiring-diagrams

Post by **taxi** » 19 Aug 2012, 15:31

A longshot from sweden then: does the car have a tow bar (right word?)? If so, disconnect the electrics in the trunk, just to be sure.
Good luck!