Can someone identify these wires?

[Michael]

I noticed a melted fuse holder in my relay compartment. I know thisbis not factory but I can't remember if installed these with my wings a loft kit or being a refurb if this is a DMCH rewired mod to maybe the headlight switch or something. I removed the melted fuse and I am gpong to replace the holder but I sure would like to know what it's for?

58493

58494

[pk2678]

Maybe this is a bypass of the fan fail module socket. It seems that a brown (brown/slate ?) cable is splitted into two inline fuse sockets going onto green/black cables. A brown/slate cable is usually going to the fan fail module. From there green/black cables are going to the cooling fans without additional fuses.
You can check if these fuses are for the cooling fans by switching on the a/c to start the fans. Two fuses -> two fans should run loud. One fuse -> one fan should run not so loud. No fuse -> no fan, silence.

--Peter

[Ron]

Fan fail mod. The Black/Green wires coming out of the fuse holders feed the radiator fans. The Black one probably replaces/ties into a Brown/Slate wire which supplies power from the circuit breaker. (It may connect directly to the breaker or plugged into the right most (passenger side) relay socket along with the Black/Green ones, where the Blue relay was originally installed.)

See Bulletin ST-06-9/82 for correct wiring.

[Michael]

Awesome. Thanks guys! The fuse holder was pretty corroded so I am assuming that is the reason it got hot to begin with.

[eight8toy]

I found your answer in this thread!

http://dmctalk.org/showthread.php?16971-Can-someone-identify-these-wires

[Michael]

I accidentally made a double post when I tried to edit one for clarity. A mod can delete one.

[Jonathan]

That fused link is here: http://store.delorean.com/p-7225-wire-link-fused.aspx

Typically, you install it in the original blue fan fail relay socket after you remove the relay from that location. If the receptacle itself is not reuseable (i.e. melted), then you can wire things up directly (as Ron was mentioning).

I think we got our cars at roughly the same time (2007 for me, but bought parts galore in 2008 and 2009). Mine wasn't a refurb but I have (had) the same fused link. And I would imagine it was made about the same time. The reason I mention that is mine just got all melty about a month ago.

Funny getting a primary colours refresher in your fuse and relay area. Guess what happens when those yellow tabs melt together with a blue relay receptacle? You get green coloured plastic! I caught it before anything awful happened thankfully. Seemed like my fans were doing weird stuff so had a look and I found the double connection had melted together into the receptacle.

Admittedly, I had seen this fused link change colours slightly on the metal ends in the past year or two but hadn't checked it super recently. I think it had gotten corroded or something and the contact surface area had gotten smaller so that same amount of current was going through a smaller and smaller amount of metal. Thus getting hotter and hotter. End result was a melted receptacle.

I redid the fused link and wired it directly together for now. I intend on putting it back like it was meant when I get my hands on a replacement receptacle. Likely a winter project.

Perhaps after seeing this a couple times now, and also knowing another owner nearby that has seen it on cars he has experience with, it should be added to the current and annual check-up of things to inspect for condition. At least once per season I would think. Like looking at your axle boots, tie rod ends, sway bar bushings and any number of other things on the car needing to be regularly inspected.

Note: there is some debate as to whether the fused part is really necessary as it seems that when the fans fail, they melt stuff before they actually blow a fuse. I think Dave Bitsync was factoring this into one of his electrical products. Not sure about details though.

[Michael]

Thanks for the info. I have been thinking about getting one of Dave's fan fail relays but the way my car is wired(mode switch controls fan rather than compressor engagement) I was wondering if it is even needed or what advantage it would have? It may not even work in my car. I didn't make it to the parts store to get some inline fuse holders. Judging by the other one, I'm going to replace both holders. It's supposed to be raining all this week so it's a good time to dive into the car for less than glamorous repairs.

[Bitsyncmaster]

Note: there is some debate as to whether the fused part is really necessary as it seems that when the fans fail, they melt stuff before they actually blow a fuse. I think Dave Bitsync was factoring this into one of his electrical products. Not sure about details though.

I did fuse testing and it turns out the BUSS brand fuses will melt and not open circuit if run a little above the rated current. Use LITTLE FUSE brand fuses and they don't melt and will eventually open circuit.

[Michael]

I did fuse testing and it turns out the BUSS brand fuses will melt and not open circuit if run a little above the rated current. Use LITTLE FUSE brand fuses and they don't melt and will eventually open circuit.

So when I replace the holders use the mini fuse holders? Or are you saying still a standard sized blade fuse and "Little Fuse" is a brand name? Should I still use 20amp or maybe drop it to 15amp?

[Bitsyncmaster]

So when I replace the holders use the mini fuse holders? Or are you saying still a standard sized blade fuse and "Little Fuse" is a brand name? Should I still use 20amp or maybe drop it to 15amp?

Little Fuse is the brand name of the fuses I recommend. Most auto parts stores sell BUSS name brand fuses. Does not mater if you use the standard or mini size. The fuse holders are what you get buying at the auto store. I would stick with 20 amp fuses which will run cooler than 15 amp fuses. The fuse is mostly just to protect from a short circuit. Fuses are not really quick enough to protect electronics or fan motors.

[David T]

Not sure what the purpose of those fuses are anyway. The original bypass that DMC offered did not include fuses and there is a circuit breaker ahead of the fuses. In any case the jumper was only supposed to be a short term solution till they could come up with a "permanent" fix! It makes me laugh to see that so many cars have been running on that stop-gap short term fix for so long! I guess it was a better long term fix than they expected. The Fanzilla was a great upgrade while it was available. If I had to do something now and couldn't get a Fanzilla I would replace the fans with newer, more efficient ones that take a WHOLE lot less power to run. Then you could probably put the blue fan fail relay back and it would not burn up.

[Bitsyncmaster]

Then you could probably put the blue fan fail relay back and it would not burn up.

I tested an OEM fan fail and to keep the fan fail light off would require 20 amps (10 amps each fan) current draw on the fans.

[Michael]

Got the holders replaced today. Used "Little Fuse" holders and fuses. I honestly don't know if both my fans were running before(never overheated) but they are both running now.

[Josh]

My radiator fans are just directly wired to the circuit breaker. Not sure the need of having in line fuses. Just gives another failure point in the system to prevent your fans from running and potentially overheating your engine.

It is also worth noting I ran a new 10 GA wire from the breaker to the fans and am running lower current fans.

[Bitsyncmaster]

My radiator fans are just directly wired to the circuit breaker. Not sure the need of having in line fuses. Just gives another failure point in the system to prevent your fans from running and potentially overheating your engine.

It is also worth noting I ran a new 10 GA wire from the breaker to the fans and am running lower current fans.

Fusing each fan protects the wiring better since the fuses are 20 amps each. With the 40 amp breaker the wiring is not so protected. Ether way if you get a dead short the fuse or breaker would open.

I removed the breaker. Like you say it's just another failure point. I send a jumper with my fan fail units to remove the breaker. That jumper (4 inches long) goes into the fan relay socket to the fan fail socket.

[David T]

I agree, the whole cooling fan electrical circuit could be a lot better designed. Two 20 amp circuit breakers or slow-blow fuses, one for each fan with a relay for each fan and a current sensing device to light a fan fail warning light and a delay so both relays don't energize at the same time. Very similar to what the Fanzilla tried to do. It's main limitation was that to be "plug and play", it had to install with minimal modifications so the breaker was retained. I don't like the breaker, not because it is too large to properly protect anything, it will reset itself and keep re energizing the circuit. If you do have a dead short you really don't want to do that except for the most critical circuits like headlights. Another way to go is a manually resettable circuit breaker but they are expensive and really not necessary. Just for the record, I have seen fan fail jumpers smoke and melt. And they had the 20 amp fuses in them! That's why I like the idea of upgrading to the lower amperage fan motors. Instead of trying to minimize the symptoms of a bad design (too much current draw in that circuit) you actually deal with the root cause of the problem.

[DMC-Ron]

An additional advantage of the fused fan fail jumpers is better redundancy. A short circuit in one of the cooling fan circuits will blow the fuse for that fan but the other cooling fan will still function. With only the breaker, it will continually reset and trip, leaving no cooling fan function. Of course with Dave's electronic fan fail relay you get the individual circuit protection along with the staggered start and fail notification, really the best of all worlds.

Ron