farawey2000
New member
I am having a problem with my 2000 Jeep Cherokee 4.0 L Limited. On the instrument cluster the key warning light stays on. I did check the all fuses and relays. It happened when my friend tried to check the oil sensor with ground after what the engine cut off and never started again and lost communication with ECM. Now there no communication with ECM. In case I will buy a used ECM from junk yard what I have to do to activate a ECM? And what about immobilizer control unit and the key?Thank you for all of you!