[Mk2] [NA] Strange, Strange, Strange! Looking for advice!

[BoJohannsen]

Hi,
Had a few problems with the electrics on my 1992 Rev 2 G-Limited recently. Been doing a lot of searching on the IMOC and MR2OC forums but have not found anything similar to my random problem. I’m hoping that someone else might have come across something similar!

My car had been run fine up until just before Christmas when if it was left for any space of time the battery went dead. I replaced the battery and after reading the forums decided that the alternator was the problem. Got hold of a new one this weekend and fitted it. Started up the car and the battery light stayed on saying that it wasn’t charging, also when I blipped the throttle the voltage gauge didn’t move.

Checked the ALT fuse in the frunk and it is okay. I know that the ECU-IG fuse is prone to blowing and this is where my strange issue starts!
I have never had an ECU-IG fuse in my car! Previously before my recent battery/alt problems the car used to run fine and charge the battery as well. If I placed a 7.5A fuse in the ECU-IG slot when I turned off the engine the radiator fans at the front of the car ran constantly and would obviously drain the battery if left alone. Take the ECU-IG fuse out and the fans stopped.

Now with the new alternator in and the ECU-IG fuse out the battery is not charging. Put the ECU-IG fuse in and the battery starts charging at the voltage gauge moves when blipping the throttle. At this moment if I turn the ignition off and remove the key the fans in the radiator come on but also the engine keeps running. I can also lock and alarm the car and the engine still continues to run.

I know this is a very random issue, obviously with the electrical wiring and it is possibly unique to my car. I am just writing to see if anyone else has experienced anything similar? Next stop will probably be the Auto electrician’s as I have exhausted all things I can think of.

Cheers,
Steve.

[silverhawk160]

Have you checked your wires to see if your getting the right amount of voltage, take out the plug that connects to the alternater (3 pin if I remember correctly) and check your getting a reading above 12 volts on all 3 with a volt meter, if your not getting 12v then the wiring is at fault. . Correct me if i`m wrong as I`m trying to remember a previous thread

[BoJohannsen]

Have you checked your wires to see if your getting the right amount of voltage, take out the plug that connects to the alternater (3 pin if I remember correctly) and check your getting a reading above 12 volts on all 3 with a volt meter, if your not getting 12v then the wiring is at fault. . Correct me if i`m wrong as I`m trying to remember a previous thread

Cheers for the reply! I've checked all that and also checked the voltage across the battery while the alternator is charging and I'm getting around 14.5 volts which i believe is correct.

It is definitely something to do with the ECU-IG fuse, I'm beginning to think it's been bypassed for some reason in the past. Got an a friend of a friend who is an auto sparky hopefully coming out to take a look at it next weekend.

At the moment the car is driveable. I just need to take the ECU-IG fuse out to switch the engine off which is a minor inconvenience!

[silverhawk160]

Sound like job for a auto sparky, soz I cant help anymore. Hope he gets it sorted for you bud