Hi guys, sorry for adding another thread on electrics, but I could find any threads with the excact same symptoms.

First of , the car is a 94 Cherokee 2,1 TD. Donīt laugh

With the car shut off, , parking lights work fine, using the headlight-switch.
If I however start the car, no parking lights, or registration plate lights.

If I turn on the headlights with the car shut off, everything also works fine.
But, If I start the car, tailights disappear, registration lights disappear and the parking light bulb in front are also gone.

-Headlighswitch was changed a month ago ( with everything working for a brief period of time )
-ALL fuses are ok, checked with a meter.

Any ideas guys?

 

Did you check the fuses under the hood in the PCM?

 

hmm, I havent!
Iīll check it first thing in the morning!
What does pcm stand for, btw?

 

Powertrain control module. Should be in the driver's side inner fender. Big fat wiring harness going to it.

 

Just diagnose problem by multimeter and test light with ignition on.

 

Thanks for the replies!

all under hood fuses are intact as well.

I guess the parking lights and licenseplate-lights are connected to the same relay, and that particular relay looses its" trigger" signal, or the "feed"(?) , when the ignition is turned on.
Perhaps the ignition switch itself is wrecked?