1992 Porsche 964 check engine light not illuminated

[Xs1ch7]

Hi all,

I recently purchased a 964 and found the check engine light to not illuminate when ignition is on.
I suspected the previous owner had removed the light bulb - however the light bulb is still installed and works (i removed the fuel pressure gauge and checked it).
I was unable to open the fuel pressure gauge after removing the 4 flathead screws. Any advice on how to do that?
Also, could you think of other reasons why the check engine light is not working?

Thank you!

[nickd]

Where are you/where is the car from? I believe that some RoW spec (M150/leaded gas models?) did not use the CEL. This functionality is supposedly not written into the chip on early models too.

[Xs1ch7]

Thanks for your reply.
The vehicle is a 1992 US model.

[nickd]

It definitely *should* be working then! I would check the pin on the harness side before getting into the gauge. The CEL pin will either have continuity to ground to illuminate the light, or it will output +12v. You'll need to use the wiring diagrams to determine which pin on the harness is for the CEL.

[ian c2]

Renowned for solder issues , do you have a multimeter ?

[Xs1ch7]

I do have a soldering iron, that’s why I tried to open the gauge, but I didn’t know how to. I just resoldered some joints on the analog clock as well.

[ian c2]

You can put continuity to the pins on the gauge .
Are you getting a signal in the wires to the plug ?