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wiring loom

Posted: Fri Mar 15, 2019 7:51 am
by peter freeman
Has anyone got a picture of the V6 wiring loom they can send me - I have a strange electric problem which originally was intermittent but is now full on. I think I have lost the -ve ( earth ) connection to the console. I can of course run a new cable but would rather fix the problem - I suspect the -ve may come in at the bottom like the other cars. Too cold and windy outside at the moment to play around so no hurry ( we are out for the day anyway ) and we do have three other Scims to use.
Regards peter - peterlfree@outlook.com

wiring loom

Posted: Fri Mar 15, 2019 8:23 am
by scimjim
My dash is out, I’ll try to get pictures today.

wiring loom

Posted: Fri Mar 15, 2019 8:32 am
by philhoward
Whilst I don't have a picture to hand, I suspect it is the braid which (I assume) goes through the tunnel and to the gearbox mount - was certainly the case on an early SE5 which had similar symptoms. Can't see a picture of the loom (or earthing arrangement) in the parts manual.

wiring loom

Posted: Fri Mar 15, 2019 8:36 am
by roymck
I’ve just had all my dash out and it looks like all earths go back the starter solenoid attachment bracket on the front crossmember . If everything else works then it can only be a broken wire or a dislodged bullet connector or bad connection . What exactly is not working on the console . I had hours of fun chasing earths so it’s only the ciggy lighter with light and heater motor that need earths coloured black down there.

wiring loom

Posted: Fri Mar 15, 2019 8:45 am
by roymck
I don’t think the braid does anything apart from linking the parts of the car together to stop radio noise . On my car it comes up through the tunnel and is connected to the radio rear mounting , it then goes along the top of the dash and goes up to the roof Ariel . On it’s journey through the car nowhere is a black wire attached to it to act as a component earth.

wiring loom

Posted: Fri Mar 15, 2019 8:53 am
by peter freeman
No radio - no battery voltage indication ( voltmeter fitted instead of current meter ) starter does not engage correctly - headlights lights come on dimly afterwards - rad fan lamp ( fitted as part of fan switch ) is on dimly even when ignition off and rad fan relay clicks on when ignition off but fan does not run. Very strange all in all but not time or weather to have a proper look and figure out what other symptoms there are. Thought at first it was a bad connection on the (new) battery but they are ok. got to be a +ve or -ve problem somewhere but separate -ve leads to engine and chassis fitted and jumped to be sure they are connected +ve leads are new to starter and fuse boxes ( 8 fuse fitted ).

wiring loom

Posted: Fri Mar 15, 2019 9:08 am
by roymck
Sounds like the earths on the solenoid on the crossmember . Have you changed to a pre engaged starter , in my car I had and the solenoid remained but both main power leads go onto one terminal . If a pre engaged starter is not kicking in then it has to be a main earth , however if you have original inertia starter then solenoid has to be earthed and this earth fixing is shared with many dash earths .
If you fitted as I have a volt meter where did you take Earth to ? Are your panel lights working?
Just to clarify what I said earlier Earth braid only earths radio casing , not used to earth radio earth wire

wiring loom

Posted: Fri Mar 15, 2019 9:25 am
by peter freeman
New high torque starter fitted - no remote solenoid. -ve lead connected directly to engine so I have to assume earth to starter is ok - ran another wire from he battery to the engine anyway to be sure. Used the black -ve wire in console to power the voltmeter. Not sure of other symptoms as I say it was intermittent until yesterday - I need to have more time to figure out what the other symptoms are and get a meter on all of the power leads in the console. Too windy to look today and going out for the day anyway as its my birthday - some present the Coupe has given me - voltage at the fuses look ok but not looked at them when trying to start the car.

wiring loom

Posted: Fri Mar 15, 2019 9:30 am
by petrolbob
Peter have you tried a battery jump lead from battery negative terminal to major metal such as engine or bellhousing? This fault affecting so many components points to a bad earth.

wiring loom

Posted: Fri Mar 15, 2019 9:31 am
by petrolbob
Sorry just read you have done that

wiring loom

Posted: Fri Mar 15, 2019 9:33 am
by peter freeman
Done already - changed the battery terminals as well. I WILL find the problem but it is so random to be sure what it is - even jumped across from battery -ve to chassis

wiring loom

Posted: Fri Mar 15, 2019 9:36 am
by peter freeman
I need to take the top off the console to find out if its the +ve or -ve that is missing. Going out for the day now - so will try not to think about it.

wiring loom

Posted: Fri Mar 15, 2019 12:43 pm
by halfpenny
IIRC, my 5a has an earth strap at a common connection for the dash earth leads, adjacent the heater valve.

wiring loom

Posted: Fri Mar 15, 2019 2:35 pm
by scimjim
Yep, I can confirm as Roy says, the v6 coupe doesn’t take its dashboard earths from the braid that runs up from the chassis to the aerial like the GTE - but has two ring terminals with 3 & 2 wires connected to the remote solenoid mount on the suspension crossbrace, running into the loom.
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wiring loom

Posted: Fri Mar 15, 2019 4:06 pm
by peter freeman
That has ll gone on my car - no remote solenoid and wire straight from the battery to the starter.