On my daily driver 1994 XJ6 I have tried replacing the DBC10009 relay before in an effort to fix a problem where my front parking lights and rear taillights do not reliably come on with the switch on the dash.
Now I am experiencing the same exact problem with the car and if I reach over and flick the DBC10009 relay with my fingers, the lights come on but they will not stay on.
I.E. if I flick the relay so they come on, then shut the switch off and back on again, the lights will often not actually come on again unless I again reach over and flick the case of the relay.
Steven, the '93-'94 MY cars-for some reason-suffer from cracked solder joints. I’d remove the circuit board from the plastic housing and look for any suspicious cracks then reflow them if I were you. I did all in my car.
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I am looking at the inside of one of my malfunctioning DBC10009 relays and I see four separate relays inside that control four separate electrical circuits.
Can anyone tell me which relay inside the case is for the running lights (front marker lamps and rear taillights) ?
They are labeled like this on the outside of the case:
1 Auxiliary Positive
2 Sidelight Positive
3 Auxiliary Sidelight
4 Cigar Lighter
but there is no way inside the case to identify which is which exactly.
Here is a photo showing the interior of the relay.
Steven, inspect visually the contact points of the relays. If you don’t see any buildup or rust then flip it to the bottom side and check all the solder joints for cracks.
Steven,
The side and tail lights are powered through relay “H3” - the “Auxilliary side lights relay”
You can identify H3 by checking the power feed wiring - Black/pink to pin 87, Blue/green to pin 30
The “Side lights positive relay” is “H2” with Brown/black to pin 30 and Brown/white to pin 87
“H4” is the “Cigar lighter relay” with Brown/green to pin 30 and Red/brown to pin 87.
I couldn’t find “H1”, the “Auxilliary power relay” in the wiring diagrams so I can’t quote the wire colours to it.
Thanks Bryan
Last night I did finally try reflowing the solder points in a couple of the DBC10009 relays I have here that were exhibiting the symptoms. I was unsuccessful with the first relay but after doing about 40 - 50 percent of the points in the second relay I now have what I believe are reliably working taillights and front parking lights.