: Fusible Links

05-22-06, 06:07 PM
Okay, so I want to replace all three fusible links that connect to the starter solenoid on my 1979 Deville. They're all like part of one harness, but I went to the auto parts store and they don't have anything like it, and I'm confused as to how exactly this should be done. There is one dark green link, and two black ones. The green link connects to a yellow wire, which I assume is for the headlamps, which will not turn on, and then one black link goes to a red wire, which I assume is for the AC, and then the other black link connects to a black wire and I don't know what that is for. The red wire for the AC does not get current, and like, when I took the link harness off the solenoid, hella water dripped out of the ribbed black plastic wire harness casing that the wires go in, which didn't give me a good feeling, so I think I'm going to replace that. I need to know where to get the right fusible link replacements though.

05-23-06, 11:36 AM
Fusible links are sized by the wire size or gauge they are attached to, not the color of the wire. The offset is 4 higher which in electrical terms is 4 sizes smaller. For example, a 14 ga wire will use and 18 ga fusible link. A 10 ga wire will use a 14 ga fusible link.

Just curious why are you replacing these? If you think they are not working the best way to determine that is a physical inspection. Do they look like they have been burned? If not, they are okay. When a fusible link fails there is usually a bright flash and sparks, hence they look like they were burned. This is why they are only used under the hood.

Hope this helps.


05-23-06, 12:35 PM
Well, they don't really look like they were burned, but I'm still not getting power from some of the lines they go to. I guess more investigation is in order.

05-23-06, 01:40 PM
Alright, well the green link, which goes to the yellow wire is clearly blown now that I've clean the grease off of it. I'm still wondering why I get no power on the red lead that goes to the AC blower relay though. It's fusible link looks fine. Also, in the book it shows the red wire going straight to the blower relay, and although the wire in the engine compartment is a very large gauge red wire, the one that actually goes to the blower relay is a smaller gauge orange wire. I can follow the red wire in through the dash, but then it disappears in a jungle of tape. Anyway, I guess what I'll do since the green link blew right at the joint between it and the yellow wire, is just cut it there and make it a little bit shorter. Then I'll clamp it with a little clamp thing, and heat shrink it.

05-24-06, 08:42 PM
Its nearly impossible to diagnos electrical problems in a forum like this. Sounds like you have some reference material do you happen to have a wiring diagram?

I'd say its safe to repair the splice you descirbed although you really need to decided if its disconnected because the solder failed or it was melted apart by over current in the wire. If you can decide splice it back to together and ghook up the battery keeping your eye on that wire in case it goes over current again and tries to melt on you. If it does and you are working with a greasy engine you could easily be working with a greasy engine that you just set on fire. Be careful.

I'd resist the temptation to hack into the group of wires you have descirbed until you are sure you know what the problem is. The blown fusible link is symptom of a bigger problem and not the problem itself. Fusible links are not like fuses that can blow from just a slight power surge it really takes some doing to fry one of those.

Let me know if you don't have a wiring diagram and I'll see if I can dig one up or come close to what you have.

Good luck.


05-25-06, 05:11 PM
Are you talking about the ones in the steering column?

I believe there is a way to diagnose the electrical system with a multimeter. On the drivers side there should be a small orange rectangular plastic receptacle that allows you to test for electrical problems.

05-25-06, 11:17 PM
Fixed it. It was the dimmer switch the whole time. I feel kind of dumb.

05-26-06, 05:38 PM
No reason to feel dumb. Electrical problems can be tough to track down and resolve especially if you don't that every day. Good job.