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Please help me with my electrical wiring issue!


SupraLEDrears

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Model 93 jspec manual Na now NA-T

 

Ecu: Initially stock, now TT with piggyback

 

Extra info: Symptoms were there before and after conversion and was present 4 years ago when I bought it.

 

So guys, since I've bought the car 4 years ago, I've had some weird interference problems. It didn't bother me before my na-t conversion but now it's messing with my gauges and idling. Here are the symptoms.

 

I get a quick, scratching noise sounding through my alarm siren everytime I open the door, turn the ignition on, turn the lights on and turn the AC blower on. This happens whether the car is on or off. When I turn the lights on whilst the car is running, my oil pressure and oil temp gauges move higher by about 1cm, when I turn them off, it goes back to normal. This also drops my RPM momentarily but I assume that's normal.

 

I have done this test with the alternator disconnected from the system too. I removed the 3 pin plug and the big wire from the alternator to do the test with the car off and the same thing happened with the clicking sound from the siren.

 

I have tested the alternator/battery as follows. Battery in boot car off, 12.7V. Car on at idle 13.99v, car at 1500rpm 14.38v. Now when I turn all the electrics on, lights, heated seats, ac, wipers, the charging voltage at idle is 11.99v but jumps straight to 14v at 1500rpm or higher.

 

This all occured even before my engine was rebuilt so I suspect a dodgy earth somewhere. Can anyone help me with some ideas for the next steps please. Thanks guys

Edited by Harrypm82 (see edit history)
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