removing redundant wiring in the loom....

[mcerbm]

I have my engine out at the moment, my car is a k-series VHPD superlight R. It originally had the MEMS ECU but now has an Emerald.

using the VHPD wiring diagram and looking through other k-series wiring diagrams i'm thinking of removing the following:

• Purge plug wiring
• IACV wiring (the IACV has been removed)
• Oil pressure sensor wiring (mechanical oil gauge)

I wasnt sure about the following if they are redundant or not:

• Alternator charging warning light (does this get used in a caterham?)
• Diagnostics line (white / yellow - pin 10 in MEMS wiring diagram) - not sure about this one if the ECU uses it? will leave alone unless someone can clarify

[Jonathan Kay]

Alternator charging warning light (does this get used in a caterham?)

Yes, that's the red ignition warning light that goes on then off when the engine starts, usually Brown/Yellow. I'm not sure but in some arrangements that might also energise the alternator.

Jonathan

[revilla]

The diagnostics line connects to the diagnostics socket in the cockpit. MEMS3 would provide ISO 9141 OBDII diagnostics on this line; not sure what the Emerald provides. ECU won't mind it being removed.

[mcerbm]

I actually found that the alternator charging warning spade was sheared and not connected to the alternator. Not sure how long it had been like that.

I'll probably keep that function if there is a warning light for it in the rev cluster (even though I never noticed it.....)

[mcerbm]

There are also a few wires that enter the engine loom plug on the engine side, but are blanked off on the instrumentation side of the loom plug. Presumably they are not used in the caterham application. Anyone else stripped these out? (Pins 1, 5, 6, 10, 12 on plug C162).

[Wrightpayne]

I'd spotted the redundant wires at the chassis / engine plug and thought the same. Being a car loom its also a bit long for the caterham application.

On my car I've routed all the power cables so they terminate at the starter so the FIA switch kills everything. When I took the engine out over winter realised the thick brown alternator cable loops right around the engine within the loom and ends up about 6" away from where it started as it now attaches to the starter motor ! I did wonder if a short cable would be better albeit would need heat sleeving.

Ian

[Ian Mackenzie]

I've just taken quite a bit out my loom....R400 race loom now with an Emerald ECU. All the wiring to the AS5, OBD now all gone...

Cheers

Ian

[OliverSedlacek]

/sites/default/files/images/users/7281/xlarge_Excess%20wire_0.JPG

That's how much wire I removed from my old XFlow loom

[mcerbm]

this is how much I have removed so far. Does anybody know what the OBD II diagnostics might be useful for? I seem to remember a few years ago trying a bluetooth type dongle connecter on the diagnostics plug and I couldn't communicate with it. Has anyone successfully used the diagnostics line before I remove it?

 

/sites/default/files/images/users/1260/IMG_2785.jpg

[mcerbm]

Decided to keep the diagnostics line and connect it into the engine loom plug (C162) as it was connected via a different type connector betweeen engine loom and instrument wiring loom. I took out the old oil pressure cable / pin as I now have a mechanical oil gauge and the pin size is different to the econoseal plug spares I have.

Does anyone know where I can get a pin for teh C162 plug from?