Help us help you. By posting the year, make, model and engine near the beginning of your help request, followed by the symptoms (no start, high idle, misfire etc.) Along with any prevalent Diagnostic Trouble Codes, aka DTCs, other forum members will be able to help you get to a solution more quickly and easily!
Good evening, I have a customer with a Grand Cherokee, the issue is with the SKIM unit. could anyone assist me with the correct test procedure or wiring diagram to help in a swift diagnosis I have autodata but there isn't any information on this vehicle that is of any use. could you give me a direction/starting point to get this car going please?
I will be going to the customer early next week so doing some research prior to going to the customer.
To get this going again you will have to tell us what exact problem you're facing: lost transponder, broken skim, "new" pcm....??
If you're in a bad need the following will probably work out.:
Start the car with carb cleaner or brake clean spraying it into the intake and keep the motor running for at least 15 seconds, even better 20 to 30 seconds. After this time the engine will keep running and the immobilizer is overwritten...but: when disconnecting the battery the immo will come backt to live.
An expert is someone who knows each time more on each time less, until he finally knows absolutely everything about absolutely nothing.
thanks for the reply, the customer has stated that the car will sometimes start but only once. if he then goes somewhere and turns off the key then it just cranks and there is a wee key symbol on the dash. I can at this point only take the customers word for this as I haven't seen the car myself as yet.
I will no more mid next week when I go see it. is this a dealer only repair or is this something I can diagnose. on the key module will there bee a supply ground and I presume some sort of signal back to the ecu?
or should I look for other info?
original ecu / pcm
both keys tried with same symptoms
possible broken skim? unsure
The transponder key is read by an antenna which in this case is part of the skim module. Any problem with the antenna not working correctly will lead to a no start. You can check the antenna with a little reader but your post makes me believe that you probably lack the tools and system knowledge to tackle this issue. You then may consider a locksmith's help/service as this problem does not require a visit to the dealership,
An expert is someone who knows each time more on each time less, until he finally knows absolutely everything about absolutely nothing.
I have a few tools at my disposal autel and snap on diagnostics pico scope and the basics as well. I just do not have any experience with this vehicle as its not within my normal car range European cars mainly. I may be able to diagnose this with my autel as it does cover some US models. what is this reader and where would you get one from please
many thanks for the assistance much appreciated
This immobilizer system is a typical one for that era, nothing special/difficult about it.
The reader is basically a coiled wire with a led soldered to its ends. You easily can make one yourself; u-tube university will show you how.....
Otherwise you can buy it on ebay etc. The link shows what it's about.
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