Relays

[MML]

We're working our way through the "stuff to do" list on the car, and here's something else I'd like to look at.
When I was waiting for my car to be delivered I did a bit of reading, and saw various articles on the dodgy original relays in the car, and how they could fail/melt/explode/go on fire etc. (delete as applicable!)

Now I'm no electrician, the best I can do is wire a plug. Here's a photo of the compartment, is there anything I should upgrade or can I rest easy?

http://i43.tinypic.com/5yumnq.jpg

[sean]

Looks pretty clean! Do you know what your circuit breakers are rated for? The rectangular silver bits with 2 posts and either 4 or 2 wires going to it next to the fuse box. You should consider bumping them up to a 30 and a 40 breaker if you have not done so yet.

[Cory W]

Remove the fuse box cover. Put it on a shelf somewhere. Also, pull every fuse, one at a time, and reseat. That helps remove any oxidization that may have built up over time (which causes electrical resistance). These two steps can help prevent fusebox meltdown.

[MML]

Not sure about the breakers; I'll see if I can find out tonight!
Several places like DMCH and DMC EU have relay upgrade kits; I wonder if what I have is one of those? It was done by a previous owner so I have no way of knowing.

Funny you mentioned the fuses; one of the sockets was partially melted but still functional, I think it was the high beam headlight fuse. Needless to say we replaced it.
What would have caused that?

[jawn101]

Not sure about the breakers; I'll see if I can find out tonight!
Several places like DMCH and DMC EU have relay upgrade kits; I wonder if what I have is one of those? It was done by a previous owner so I have no way of knowing.

Funny you mentioned the fuses; one of the sockets was partially melted but still functional, I think it was the high beam headlight fuse. Needless to say we replaced it.
What would have caused that?

Doesn't look like an updated relay kit to me. I'd do a full relay update anyway, it's only like $150 and well worth the peace of mind.

Melted fuses are caused by bad connections and over-drawing current. The OEM fuse box is known to do this because the contact material in the terminals is weak. You should consider replacing the whole fuse block with an updated one that has better materials. Lots of info on the forum here on how to do that.

[dmc6960]

Doesn't look like an updated relay kit to me.

Huh? Thats exactly what the highlighters indicate, that it ALREADY has been updated. Only thing that is unsure of here is the circuit breaker ratings, but I'd say its a very safe bet those have been done too looking at everything else.

[jawn101]

Huh? Thats exactly what the highlighters indicate, that it ALREADY has been updated. Only thing that is unsure of here is the circuit breaker ratings, but I'd say its a very safe bet those have been done too looking at everything else.

You're right, I forgot Houston had that other kit with the standard relays, I was only thinking of the 'updated' purple/black cased ones. My mistake!

[Farrar]

You can replace the "fused jumper" in the blue Fan Fail Module Socket with one of Dave McKeen's new units. Apart from that it looks good to me!

Farrar

[jawn101]

You can replace the "fused jumper" in the blue Fan Fail Module Socket with one of Dave McKeen's new units. Apart from that it looks good to me!

Farrar

I'm jealous of the blue socket, actually. And it looks like your defrost timer has a green socket, and Lambda has a yellow one? Yeesh. Mine are all black (except the red and white ones) and have tiny colored sticker dots on them.

[Elvis]

Here's a photo of the compartment, is there anything I should upgrade or can I rest easy?


I can't repeat it often enough !

The minumum you have to do for your power locks it to add a 10A fuse in the fat red wire from the Door Lock ECU !!!

melting fuses - what high beam bulb do you have ?

the closer the current is to the fuse's rating, the hotter it gets !
Fuse sould be reated 50 to 100% above the regular current to work cool.
Yeah I know big discussion starter, but I measured the temperatures to prove it.

[David T]

As long as we are talking about the fuse-block/relay area here is a list of things:
Make sure there is NOTHING plugged into the hot start relay plug
Add the 10 A fuse to the big red wire for the lock module
Uprate the cooling and heater fan circuit breakers and some relays with the relay upgrade kit
Remove the courtesy light delay relay
Remove the fuse cover, place it nearby with some extra fuses in it
Add a jumper to make the console lights only light when the headlights are on
Make sure each fuse is the correct size for it's spot.
Make sure all of the connectors are gripping the fuses tightly
Check for any heat damage and replace the connectors if overheated
Do the mod on the door lock module to reduce the standby current draw
Add a battery master switch
DMCH has a nice decal to apply to the wood cover identifying each fuse and relay
David Teitelbaum

[leroyvette]

David T's reply---
Add a jumper to make the console lights only light when the headlights are on--
David----this sounds like a good idea---where do you make this jumper connection?

[David T]

I don't have the info immediately available, I am sure someone will offer it quickly. You pull a relay and stick a jumper wire in. Keeps the plastic console display a lot cooler. You don't really need it to light up during the day.
David Teitelbaum

[jawn101]

David T's reply---
Add a jumper to make the console lights only light when the headlights are on--
David----this sounds like a good idea---where do you make this jumper connection?

Proving David right...

http://www.dmcnews.com/Techsection/acpanellites.htm

[DMCNY]

DMCH has a nice decal to apply to the wood cover identifying each fuse and relay


Do you have a link to that? I couldn't find it on the site.

[MML]

Guys - many thanks for the replies! I'll get some more pictures tomorrow and try to answer some of the comments! Bear in mind I'm a complete beginner at this sort of thing! :frown:
Oh and that bit about the air con panel lights seems a great idea, there's a lot of bulbs in there!

What I can tell you now is, I just had a quick look, the circuit breaker values are as follows:

#19: 25A
#20: 40A
#36: 40A

(see diagram for location)

Also there is a cutoff switch for the battery, I usually keep it disconnected when the car's in the garage.


For some reason I can't see my original picture, nor can I edit my post so here it is again just in case.

http://i.imgur.com/MN5BL.jpg

http://i.imgur.com/4FvQG.jpg

[DMCNY]

http://i.imgur.com/MN5BL.jpg

http://i.imgur.com/4FvQG.jpg

I have a question about the two breakers located side by side (#20 & #19)

My breakers are in the same position as pictured in MML's fusebox. The one with the two wires (black/orange & brown/orange) is positioned closest to the drivers side.

According to the diagram, that one is supposed to be the blower motor breaker (#19) but isn't the two wire breaker actually supposed to be the cooling fan breaker?

Just curious if the diagram is wrong, or if we both have our breakers in the wrong position.

[jawn101]

I have a question about the two breakers located side by side (#20 & #19)

My breakers are in the same position as pictured in MML's fusebox. The one with the two wires (black/orange & brown/orange) is positioned closest to the drivers side.

According to the diagram, that one is supposed to be the blower motor breaker (#19) but isn't the two wire breaker actually supposed to be the cooling fan breaker?

Just curious if the diagram is wrong, or if we both have our breakers in the wrong position.

Pretty common for those to get swapped around after years and years of maintenance. They just clip into place after all :) The lucky thing is that it's pretty easy to identify which is which. Mine were backwards as well when I got the car, but when I redid the electrical compartment I put them back where they're "supposed" to be, for ease of identification later.

[DeLorean]

In my car, the 3 circuit breakers are removed and replaced with their equivalent fuses.

Not a terrible idea to go to an auto parts store that has new Buss brand blade fuses and replace all the fuses. I know fuses should never "go bad" but I had several fuses in my panel that had a noticeable amount of oxidation on the blades, which apparently in DeLoreans can contribute to fuse box melting problems.

[jawn101]

Not a terrible idea to go to an auto parts store that has new Buss brand blade fuses and replace all the fuses. I know fuses should never "go bad" but I had several fuses in my panel that had a noticeable amount of oxidation on the blades, which apparently in DeLoreans can contribute to fuse box melting problems.

Houston actually recommends full replacement of all blade fuses every year as part of a preventative maintenance program. Probably $15 well spent.

[David T]

Replacing every year is probably overkill. They should be checked annually at least. The whole area should be watched for heat damage, all too often owners don't even know about this area and neglect it till something goes wrong!
David Teitelbaum