Electrical puzzle

[Davo1805NZ]

Hi everyone - I have recently lost power to a whole load of things - tacho, fuel & temp gauges, brake lights, indicators etc. Fortunately this didn't happen while out driving, just when I came to take the car out after not having used it for a few weeks. Simplistically it would all relate to a problem with the Ignition Control circuit, however there is power at the fuse and the fuse is good. There is no power at the 9-pin connector where the dashboard loom joins with the main loom, and checking with a meter for continuity of the green wire from the connector back to the fuse board, there is none. Seems that there is a break somewhere in this relatively short, straightforward path, but where and why? The wiring was all new when I put the car back together and everything has been working fine for a couple of years or so, until now. Does anybody have any suggestions for where to look next? Am I missing something fundamental?

Thanks in advance for any advice offered. Cheers - Dave

[jbuckl]

Fuse rivets gone loose? Possibly?

Time to use an ohm-meter… analogue not digital preferably…. Wobbly needle indicates poor continuity / connectivity….. most likley on fuse 1/2 or battery control relay.

[jbuckl]

Multiple errors on saving this message…. Apologies. The forum editing or WiFi connectivity is poor.

[wilf]

Also, a fuse can "look" OK, but actually be OC.

[trunt]

All comes back to fuse 3/4 so +1 on check fuse with meter.

I would go to the back of the fuseholder, inside the car. check the wires are still on the terminals and check for voltage at the terminals. The original fuseholders have a habit of going open as the rivet holding the fuse clip comes loose. As your stoplights are also not working the connector at the console is probably not the issue, the stoplights are directly wired to the fuseholder and there does not seem to be any plugs that feed both circuits.

[Davo1805NZ]

So after pulling out the parcel shelf and glovebox I discovered that the green wire from fuse 3/4 is routed back in the loom through the fuse for the wipers, and this fuse had blown. This is not per the wiring diagram, and also differs from the car’s original loom, which I had been using as a reference. Strangeâ€Ĥ Still have no indicators - think this may be the flasher relay.

[trunt]

Strange, the wipers and washers should be the only ones on fuse 19/20, the rest on fuse 3/4. They are Separate green wires. Could the two green wires at the fuse box be swapped? Both of those fuses are fed by white wires at the supply end, .linked together.

Pic below, its a Federal but should be similar. Note the double greens to fuse 19/20 (that's what the cct. diagram shows as well) and single to 3/4 there is a single white wire that links the two fuses together.

(sharper people will notice that fuse 17/18 for the dipped lights is disconnected.. and the blue/pink is swapped over to 16.. I corrected that when I got a new fuseholder!)

IMG_2810.jpg

[Davo1805NZ]

Yes I have that Terry - single green wire to 3/4 and double green wires to 19/20. But with no fuse in 19/20 there is no continuity between the single green wire and the connector in the top of the dash - and hence no power to tacho and voltage stabiliser. Checking on the old loom this continuity exists with no fuse in 19/20. The loom in the car is one that I bought about 3 years ago from one of the suppliers (Rimmers I think).

[trunt]

One of the two on 19/20 should be on 3/4?

One of those two wires on 19/20 should run the wipers, the other the washer pump, are either of those not working when the 3/4 fuse is pulled? That would mean that the green wire on 4 should be on 20 and one of the two on 20 should be on 4

[jbuckl]

One of the two on 19/20 should be on 3/4?

One of those two wires on 19/20 should run the wipers, the other the washer pump, are either of those not working when the 3/4 fuse is pulled? That would mean that the green wire on 4 should be on 20 and one of the two on 20 should be on 4

Wow, you could only get that info here !

[trunt]

Wow, you could only get that info here !

Or look at the circuit diagram.. I do use a colour diagram for overview but this is the reason I always defer to the ones in the ROM as they are pretty literal on how the car is actually wired..

[Davo1805NZ]

One of the two on 19/20 should be on 3/4?

I will check that Terry. The loom is as I received it from the supplier; i.e. with the two wires currently on 19/20 spliced together into a single spade connector, so that is how I installed it, which is similar to how the old loom was installed. However, I did previously discover another issue with this new loom back when I was initially commissioning all of the electrics - two of the pins in the 3-pin connector at the top of the dash were transposed, causing some head-scratching when trying to get the indicators working. So I guess it's feasible that there's another cockup there.

Speaking of indicators - in my original post I mentioned that these had also stopped working. I found that to be totally unrelated, being the LG/N wire in the stalk having broken off the central tag - resulting in my spending an enjoyable (not!) time yesterday dropping the steering column etc. to get the thing on to the bench to solder the wire back in place.

[jbuckl]

I will check that Terry. The loom is as I received it from the supplier; i.e. with the two wires currently on 19/20 spliced together into a single spade connector, so that is how I installed it, which is similar to how the old loom was installed. However, I did previously discover another issue with this new loom back when I was initially commissioning all of the electrics - two of the pins in the 3-pin connector at the top of the dash were transposed, causing some head-scratching when trying to get the indicators working. So I guess it's feasible that there's another cockup there.

Speaking of indicators - in my original post I mentioned that these had also stopped working. I found that to be totally unrelated, being the LG/N wire in the stalk having broken off the central tag - resulting in my spending an enjoyable (not!) time yesterday dropping the steering column etc. to get the thing on to the bench to solder the wire back in place.

AKA new looms are not a panacea?

[trunt]

Keep us posted, I would imagine the looms are hand made and it would be easy to get the three green wires mixed up when crimping the spades on.

[jbuckl]

Keep us posted, I would imagine the looms are hand made and it would be easy to get the three green wires mixed up when crimping the spades on.

AKA new looms are still not a panacea?