Dashboard light off and on

ProjectS90 · Post by **ProjectS90** » 21 Feb 2018, 21:55

Hi,

Looking for advice for a 1998 Volvo S90. Bit background,I switch light switch and check fuses. The lights on dashboard turn off and on and most of the time stay off when turning lights on, then all a sudden turn back again for a bit to then go off again. The lights go off in the instrument panel, radio and air control unit. All gauges work at the time lights go off, meaning speed, temperature etc gauges. I switched the dimmer switch to an used one nothing. Also the high beams don’t go on when I turn on the switch,I replaced the switch and nothing high beams will not turn on. I’m thinking could be a relay but not sure, because the lights go out across the whole dashboard.

Any ideas on what could bring?

Ed.

Post by **RickHaleParker** » 22 Feb 2018, 01:39

Try the overload relay. Cab fuse box, bottom relay.

ProjectS90 · Post by **ProjectS90** » 22 Feb 2018, 10:12

Thanks Richhaleparker. I’ll post if that fix that problem. Cheers

ProjectS90 · Post by **ProjectS90** » 22 Feb 2018, 10:12

Thanks Richhaleparker. I’ll post if that fix that problem. Cheers

lummert · Post by **lummert** » 22 Feb 2018, 11:18

The main headlight relay can cause head scratching issues.

ProjectS90 · Post by **ProjectS90** » 23 Feb 2018, 16:16

Hi.

Follow up, changing the overload relay on main cab fuse box didn't help. The light on dashboard still not lighting, the light switch when switch on (not the daytime light) work, headlights work. The lights on instrument cluster, radio, air control unit are not turning on at all. All of the gauges work, speed, temp, fuel and clock are running. Only the light that illuminate all of the dashboard light go off. The temperature electronic dial also work on the S90 lower left hand.

Trying to do a DYI but can't seem to pint point the problem. There's two other fuse/relay boxes inside the hood could there be another relay that is causing this? Any more hints to check really appreciated. Could it be a faulty instrument cluster?

Post by **RickHaleParker** » 23 Feb 2018, 18:22

That last write up is contradictory.

lummert · Post by **lummert** » 23 Feb 2018, 18:48

Wiring diagram for 1997 960 shows main headlight relay is behind dash, left of steering column. Diagram also indicates that the headlight switch and the main headlight relay grounds run to under the left front seat. Looks like the headlight switch grounds the indicator lights through the black ground wire that runs from the switch to under the left front seat.

ProjectS90 · Post by **ProjectS90** » 23 Feb 2018, 22:17

Hi lummert.

Thank you, so your are saying there’s a possible ground issue? How can that be fix? The left seat was replaced sometime during the life of the car, it doesn’t has the original left seat so something unplug or not grounded?

This car is a project has a solid engine with only wear and tear repairs/maintainer issues so inside is the only issues it has, the lights of entire dashboard do on and off and mostly stay off.

Thanks again

Ed

jetdog · Post by **jetdog** » 30 May 2020, 16:14

Anyone have experience with the instrument cluster lights not functioning with headlights on.
I have replaced the light intensity adjustment reostat and still no function.
Any suggestions or ideas appreciated.