Mitsubishi Montero Sport No Start

Michael Mobile Technician Utah Posted   Latest  
Tech Tip
2004 Mitsubishi Montero Sport LS 3.5L (R 6G74) 4-spd
Crank / No Start

I was called to a shop that had a no start condition in a Montero Sport. It had been DIY'd before going to shop. Many parts had been swapped. Customer had installed used immobilizer. When I got there the immo lamp was on. I tried to use the relearn process in the AutoProPad but the vehicle was not having it. It reset the immo fine but the key would not learn. I took the part number off the key and did a Google search. It was a clone key. I did not have the proper key in my inventory. We got key from locksmith and it programmed fine. Still no start. It had an immo communication code. After testing communication wire, grounds and power the shop determined that there was an issue with the PCM. They got a used one on eBay. I came out a second time. Reset the immo and again learned key. Still the same. I suggested we install the original immo and PCM and try to learn the new key. Reset and relearned key with AutoProPad, Success! So the key was the issue all along.

Apparently, the PCM has a seed key similar to what you see in other vehicles. The immo and PCM need to be mated. We could have cloned the EEPROM if the original PCM was toast as a next step. Fortunately we were able to return to stock and get it going. Good thing all the parts were still there. After discussing with the shop, it was found that the immobilizer was out of a different model and not a Montero Sport. The part number was the same as the original. Not sure how that complicated things.

My tips for the day...

1) Keep all the parts until the repair is confirmed. I can't tell you how many shops send back cores once they get the replacement.

2) When the results are not making sense. Go back to the beginning and start over. You missed something.


Paul Diagnostician

My skin crawls when the core goes back early.... great post brother.

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Daryll Diagnostician

Recently got called to flash a replacement ecm in an 05 Mazda Tribute. Shop had already installed the replacement module (used), and was going to perform a PMI procedure but the original module had already been returned. Next problem was that the used module was a no comm. Powers, grounds, comm circuits fine, module was producing 5v ref to sensors. Terminating resistor ok. Tried 2 different…

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Dean Owner
New York

Mike, Thanks for sharing this. I am curious as to your opinion on the autopro pad? How does it compare to advanced diagnostics MVP pro? Are you happy with the autopro pad? I am very close to purchasing one. Thx, Dean

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Michael Mobile Technician

Dean, I am very fond of the tool. I purchased it mainly for Chrysler vehicles. I like it so much I became a dealer. It has been very useful for Chrysler. It does not yet read Pre-CAN skim codes. It will program pre-CAN if you have the code. CAN vehicles are very well covered, even the 5 digit codes. I have the MVP. It is a good tool. The MVP tokens are the problem. $40 per token is a heavy…

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