Fog Light Switch Question

N2M03Mach · 10-14-2009, 08:26 PM

What would cause the fog light switch to stay on? It first would not ever come on (no fog lights either) and after swapping relays under the hood. The light stays on? I have not checked the bulbs, but I find it had to believe both went out at once?

Thanks for the help.

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PROMETHEUS PRIME · 10-15-2009, 01:39 PM

Could be you put in a bad relay

USMCrebel · 10-15-2009, 01:50 PM

^ above...not all new parts work. i found that out with my 67 302'd car with alternators.

N2M03Mach · 10-15-2009, 05:59 PM

No, I just moved relays around in the fuse box. I have two of one, and three of the other. I just did a swap for quick troubleshooting. I will be testing the voltages soon. I will keep you posted.

N2M03Mach · 10-17-2009, 04:38 PM

Well, both bulbs were blown. Now I cannot get the lights to turn off. If I hit the switch, it does kill them, but only for a second. Any suggestions?

PROMETHEUS PRIME · 10-17-2009, 07:04 PM

It's sounds like the circuit is grounding somewhere being completed. If you unplug the swicth do they shut off? I would check the connectors of the bulbs and swicth for being melted or anything

N2M03Mach · 10-17-2009, 10:59 PM

Both the connectors and the switch seem to be fine, as in, nothing is melted... At this point I think it is the switch.

PROMETHEUS PRIME · 10-17-2009, 11:05 PM

Yeah. If you know anyone with a mustang switch the switches and see if the problem switches too

cwf340 · 10-29-2009, 07:08 AM

here is the ford pinpoint test for foglamps, hope it helps.

CHECK THE FOG LAMP RELAY
Disconnect: Fog Lamp Relay.
Are the fog lamps off?
Yes
GO to Q2.

No
REPAIR circuit 478 (TN/OG). TEST the system for normal operation.
Q2 CHECK FOG LAMP RELAY
Check the fog lamp relay.
Refer to Wiring Diagrams Cell 149 for schematic and connector information.

Is the fog lamp relay OK?
Yes
RECONNECT the fog lamp relay. GO to Q3 .

No
INSTALL a new fog lamp relay. TEST the system for normal operation.
Q3 CHECK FOG LAMP SWITCH
Disconnect: Fog Lamp Switch C240.
Are the fog lamps off?
Yes
INSTALL a new fog lamp switch. TEST the system for normal operation.

No
REPAIR circuit 188 (WH/BK) for short. TEST the system for normal operation.

cwf340 · 10-29-2009, 07:11 AM

if I was gonna guess, I would say the relay you switched was differant. try switching them back first. of replacing it. I would also suggest only using a ford relay. my exp. with aftermarket electical parts is they are junk.