Dash Lights-Dimmer??? (68 B) - Moparts Forums

Register Log In Moparts Forums Moparts Question and Answer Dash Lights-Dimmer??? (68 B)

Print Thread

Dash Lights-Dimmer??? (68 B) #1189826 03/02/12 07:45 PM 03/02/12 07:45 PM
Joined: Feb 2003 Posts: 252 L.A., CA P plysat OP enthusiast
plysat OP enthusiast P Joined: Feb 2003 Posts: 252 L.A., CA	Here's a fun one... The other night my dash lights were out, so I thought I'd fiddle with the thumb wheel dimmer and... no effect on the dash lights but at a certain point both TS indicators and the oil idiot light indicator came on... ??? The dome light still comes on and off as it should. Any ideas? Bad thumbwheel dimmer? It's a weird one. Thanks!

Re: Dash Lights-Dimmer??? (68 B) [Re: plysat] #1189827 03/02/12 08:13 PM 03/02/12 08:13 PM
Joined: Nov 2004 Posts: 9,312 SoCal 68HemiB master
68HemiB master Joined: Nov 2004 Posts: 9,312 SoCal	Quote: Here's a fun one... The other night my dash lights were out, so I thought I'd fiddle with the thumb wheel dimmer and... no effect on the dash lights but at a certain point both TS indicators and the oil idiot light indicator came on... ??? The dome light still comes on and off as it should. Any ideas? Bad thumbwheel dimmer? It's a weird one. Thanks! Symptoms like this often have as their cause an open ground side of the circuit. What happens is that the current is finding an alternate path to ground, through the filament(s) you describe. If the engine was running [and had oil pressure] at the time, that portion of the symptoms is not so obvious. The turn signal indicators fit with the textbook "common ground open, feeding back through filament(s) to an alternate ground" scenario. If you check the printed circuit on the back of the cluster, you should be able to trace the common ground, and clean or reconnect or provide an alternate connection to a solid ground somewhere on the dash frame or firewall. This is not to say that dimmers in 45 year-old cars aren't prone to open/dirty rheostats. It's just that your symptoms point to a grounding issue. Down to just a blue car now.

Re: Dash Lights-Dimmer??? (68 B) [Re: 68HemiB] #1189828 03/02/12 09:08 PM 03/02/12 09:08 PM
Joined: Feb 2003 Posts: 252 L.A., CA P plysat OP enthusiast
plysat OP enthusiast P Joined: Feb 2003 Posts: 252 L.A., CA	That'll be fun ... this may be a silly question, but the last time I was in the car I hit the high beam switch, which I probably haven't done in years. I've heard those can cause weird problems too. Possibility? I do have a new PC board, and I probably should get a new thumbwheel dimmer as mine has been sort of funky for the 20 years I've owned car, but never anything like this...

Re: Dash Lights-Dimmer??? (68 B) [Re: plysat] #1189829 03/03/12 12:46 AM 03/03/12 12:46 AM
Joined: Nov 2004 Posts: 9,312 SoCal 68HemiB master
68HemiB master Joined: Nov 2004 Posts: 9,312 SoCal	The fault is probably NOT on the printed circuit itself (end even less likely in light of its recent replacement), but in WHERE THE GROUND TRACE of that printed circuit connects to the dash frame, especially in light of the recent meddling in that very area. The high beam switch has nothing to do with this. It's not voodoo. really. Down to just a blue car now.

Re: Dash Lights-Dimmer??? (68 B) [Re: 68HemiB] #1189830 03/03/12 01:16 AM 03/03/12 01:16 AM
Joined: Mar 2003 Posts: 18,678 Fresno, CA Jim_Lusk I Live Here
Jim_Lusk I Live Here Joined: Mar 2003 Posts: 18,678 Fresno, CA	Quote: It's not voodoo. really. You are quite correct. It's magic (but a special kind that I can't say on here......).

Re: Dash Lights-Dimmer??? (68 B) [Re: 68HemiB] #1189831 03/03/12 01:34 AM 03/03/12 01:34 AM
Joined: Feb 2003 Posts: 252 L.A., CA P plysat OP enthusiast
plysat OP enthusiast P Joined: Feb 2003 Posts: 252 L.A., CA	Heh... thanks, I actually haven't replaced the PC board yet... Was trying to avoid diving into that... I'll trace the ground first... I'm actually not too bad with electrical witchcraft, it's the laying upside down in a pretzel shape trying to trace wires that I'm getting tired of. Quote: The fault is probably NOT on the printed circuit itself (end even less likely in light of its recent replacement), but in WHERE THE GROUND TRACE of that printed circuit connects to the dash frame, especially in light of the recent meddling in that very area. The high beam switch has nothing to do with this. It's not voodoo. really.

Re: Dash Lights-Dimmer??? (68 B) [Re: plysat] #1189832 03/03/12 02:06 AM 03/03/12 02:06 AM
Joined: Mar 2003 Posts: 18,678 Fresno, CA Jim_Lusk I Live Here
Jim_Lusk I Live Here Joined: Mar 2003 Posts: 18,678 Fresno, CA	If there's that much work to do on your backside, remove the front seat. Believe me, the time spent pulling the seat will be worth it.

Moderated by Al_Alguire, Hotwheelsjr, moparts, not_a_charger, RangerDan440, tboomer

Hop To

Powered by UBB.threads™ PHP Forum Software 7.7.1