dozybee

This is mainly for persons of an electrical bent. Has anyone actually had a look in the interior of the relay/ fuse panel ?. I had to jumper my Horn/hooter wiring
from plug E pin E11 to plug A pin A7,thence to pin A3. According to the assorted schematics pin E11 was supposed to go to A7 within the fuse panel ??
The car horn now functions properly. How many disconnects are lurking beneath the surface of the fuse panel ???
I am suspicious as the car cuts out intermittently as well and the soldering/hot/cold/DME routine has revealed nothing.

Gage

None of my early cars have had hooters The horn wiring however is a common fault amongst others within the central electric assembly.
The CE assembly is comprised of layers of buss bars separated by plastic insulation plates, the fuses, the relays and the harness plug connections are all linked by the buss bars. The harness plug connectors are mostly small diameter pins, soldered on to the buss bars. This is the most common point of failure and they fail in two ways. One failure is a burned surface of the pin, probably from oxidation and increased resistance between the pin and the female plug. The second failure is that the pin breaks off from the bar. Either of these failure modes can be intermittent.

Gage

Correction, the pins are mechanically engaged (swaged) with the bus bars.

orig944

Gage

This is a late CE panel in the video. The early car the OP is working on has a completely different assembly.

orig944

I know. This was to show how they are constructed.

dozybee

Thanks for the replies. The pic of the old type of fuse panel was very informative. Regretfully, I was a few months away
from the model with the newer, external fuse/relay panel. Does the panel need to be destroyed to disassemble it or
can it be meticulously stripped and repaired ( A scrapper could be just as useless ).

Gage

I think an early CE could be dis-assembled and re-assembled, but it would be neither fun nor easy. Perhaps start with removing it from the car to clean and bench test the pins, relay sockets and the fuse contacts. Broken pins can be identified by attempting to rotate them, burned pins can be scraped with a small screwdriver. In chasing an engine cut out, keep in mind the majority of the CE function serves the chassis components and is not critical to engine run signals. Power is supplied to the DME and to the fuel pump, those are (from memory) about the only engine run signals going through the CE. The fuel pump fuse and contacts are common failure point. Clean and polish all the contact surfaces and add some deoxit to each connection.

orig944

If you value your time at any reasonable rate, it might be better to source a used panel. I looked through the PETs and found that early 944s and all 924s share the same part, so availability of a good one is likely very high.

dozybee

As well as fixing the hooter wiring I have now spliced some other wiring together to unload some of the pinouts. Time
will tell.