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fog light diagnostic help

Old 08-26-2015, 09:52 PM
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fog light diagnostic help

ok so after trying to convert the bulbs in my fog light switch to LEDs my fog lights don't work anymore . Also the panel lights (lights inside the switches that illuminate when its dark out) for the fog light switch and the headlight switch don't come on anymore.

ALL FUSES ARE GOOD. pulled every one of them out and inspected with my own eyes. Headlights work low and high beam, headlight doors open and close as normal. So i've been going through the 4 step diagnostic proceedure in the FSM under "headlights with monitor: fog lights". measuring at the fog light relay connector, steps 1 & 2 both test good, but steps 3 & 4 do not have proper voltage ( supposed to be at battery voltage). if i recall correctly, step 3 is measuring between the red/white wire and ground, & step 4 is measuring between the red/white and purple wire. FSM says i have to check FUSIBLE LINK G for condition. that fusible link also connects to the red/white wire that didn't read battery voltage. so i dig for the link and this is what i find...



Now i've never dealt with fusible links before, and i found the link finally when i was done for the night, but i need advice diagnosing this problem. From what i've read fusible links burn up when over loaded, and this doesn't look burnt or damaged. i will take some voltage measurements at the link tomorrow when i have more daylight and mosquitoes aren't eating me alive.

Thanks in advance!
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Old 08-27-2015, 09:21 AM
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Re: fog light diagnostic help

anybody?
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Old 08-27-2015, 08:33 PM
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Re: fog light diagnostic help

Just FYI, the fusible link looks like a regular wire (or pretty close). The insulation is specially made so that the wire inside can melt and cause an open without melting through the insulation and causing a fire. I'm not exactly sure what that's a picture of there, so I can't say if it would be something to check out or not. Does the FSM give any indication about the location/color of fusible link G? It sounds like you at least have a pretty good idea of troubleshooting procedure, so that's a good start .
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Old 08-27-2015, 09:56 PM
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Re: fog light diagnostic help

Well i'm glad SOMEONE responded lol Thanks!

What you are looking at are 3 fusible links, one of them being fusible link G (specifically the rust colored wire with the blue butt connector on it. The 2 blue wires are fusible links for the headlights. Now TGO actually has a picture of these links!

Today i determined that the fusible link was at fault for the fog lights not working (no continuity through the splice on the link). As a temporary fix, i cut out that blue butt connector and re-spliced the link. Fog lights work again!

Well, this was only a half victory, as the panel lights for the fog light switch and the headlight/dimmer switch still do not work. I bench tested the panel light circuit for the fog light and the bulbs are dead inside the switch. So either A) i'm going to find another switch or B) solder in new, incandescent bulbs.
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Old 08-28-2015, 09:04 AM
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Re: fog light diagnostic help

Looks like you already knew whats up. It's hard to gauge knowledge levels sometimes. Didn't you already replace the bulbs with LEDs, or was that a different car?
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Old 08-28-2015, 10:30 PM
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Re: fog light diagnostic help

Yeah i have knowledge, but not with fusible links. it was a good learning experience.

I replaced the bulbs with LEDs on my old fog light switch. then when the fog lights stopped working i bought another switch off ebay. Thing is the one i bought off ebay has bad bulbs inside too. neither panel nor indicator. I may try and solder in some new incandescent bulbs from radio shack.
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Old 08-28-2015, 11:04 PM
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Re: fog light diagnostic help

Didn't radio shack go belly up?
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Old 08-29-2015, 12:15 PM
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Re: fog light diagnostic help

yeah they filed for bankruptcy and many locations closed, but they are still around, Thankfully. The closest one to me now is 15 minutes away.
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Old 09-08-2015, 08:23 PM
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Re: fog light diagnostic help

Just as conclusion for this thread, the problem here was fusible link G. Repaired the fusible link, Fog lights work again. Happy Happy.
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Old 03-15-2019, 11:40 AM
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Re: fog light diagnostic help

Is not the fusible link in the 6 in
tube next to the starter?
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