dashlights issue 97 850 RESOLVED, loose connector

wilson850r · Post by **wilson850r** » 02 Jun 2012, 10:55

Have replaced rheostat dimmer switch and bad ignition switch and still no dashlights. Warning lights come on as do lights by window switches. Sunroof is working so fuse for lights is good. This is my third 850 with dashlights problems. Both other two were fixed by replacing the dimmer switch. Any suggestions will be appreciated.

Post by **rspi** » 02 Jun 2012, 15:39

Are you sure you have a good dimmer switch? If so, I guess it's time to break out an ohm meter.

Post by **rspi** » 02 Jun 2012, 15:42

Are you sure you have a good dimmer switch? If so, I guess it's time to break out an ohm meter.

Post by **BEJinFbk** » 02 Jun 2012, 17:07

+1 on the high probability of a bad dimmer unit. It wouldn't be the first...
I'd use that meter to look for juice and a good ground coming into it.

Ign switched 12 volts shows on a Brown/Orange wire at pin 1
Switched 12 volts from the headlight switch - White at pin 3
Ground comes to the dimmer on a Black wire at pin 2

The dimmer output leaves the dimmer unit on Pink from pin 4.
If you see all three, with nothing out on the pink wire, try another dimmer.

( Looks like the headlight switch also shows the dimmer
a switched ground on White/Black wiregoing into pin 6.
That only connects in the headlight switch's off position,
so I would tend to doubt that it's involved in your problem. )

The headlight switch shows as 3/2 in these
diagrams and the dimmer unit is shown as 4/4 :

95 850 dash illumination.pdf: (420.31 KiB) Downloaded 234 times

wilson850r · Post by **wilson850r** » 02 Jun 2012, 18:53

Thanks for the info. Bought the switch this time direct from Volvo, yes paid big bucks. We were hoping it was the ignition switch which was bad so was hoping that would solve. Sounds like it will be a long weekend.

wilson850r · Post by **wilson850r** » 05 Jun 2012, 11:36

Update on this problem. Have power coming out of rehostat switch but everything seems to stop at cluster. It has the VDO guages. The fuel guage only goes to 3/4 full. Have not checked the sending unit but am I looking at a bad cluster?

Any suggestions where to go next. I did replace the ignition switch and have power coming out of it and out of switch. Just still no dashlights.

Post by **rspi** » 05 Jun 2012, 18:35

I started having dash problems about a couple of months ago. Tested several things and it ended up being the wires on top of the cluster plug. The weight of the wire harness was putting so much pressure on top of the cluster plug wires that the wires were broken inside of the plug harness. I got a plug from the junk yard and spliced it together. I must have a couple of bad splices because I have a couple of different issues now.

drtrance · Post by **drtrance** » 06 Jun 2012, 00:06

Thanks for the info! I'll try to find out what's ging on with my dashboard lights.

wilson850r · Post by **wilson850r** » 11 Jun 2012, 23:39

Thought maybe it was the headlight switch but still no dashlights. There is a black and white wire that comes out of both headlight switch and rehostat that I believe should have power but seems to be grounded. It appears the pink wire carrys all power to lights.

I unplugged the cluster but no difference in any areas of power.

Any suggestions on where to go next?

Post by **BEJinFbk** » 12 Jun 2012, 01:53

Is there power on the pink wire?
Does it vary when you adjust the dimmer?
Any chance you have a bunch of burned out bulbs?