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AAM/ignition or CPK?

1445 Views 13 Replies 5 Participants Last post by  Astani
My 1999 ML320 with over 220K has been running great till yesterday. Went for shopping, and when I start the car just crank two or three times. I tried too many times and the same happen. Check the battery, Disconnect/Connect it and the same issue. Used a booster and same thing happen, it crank two or three times and does not start.
Tow my car to driveway and let it for a while. Check the ODBII, no check engine, no other errors. The car lock/unlock normally. Check all interior/exterior light and wipers and everything working fine.
Tried again, and suddenly the car start normally, I shut it off and tried again. The same thing happen, crank two or three times and does not start.
With a key on the position 1, there was no blinking.

I tried again today in the morning, with the key on the position 1 the blinking was normal and in the position 2 just once. Start the car normally and left it till reach the normal temperature 80 C. Restarted three more time after that and everything seems to be normal.
Anyone can shed some light, what it might be?

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Please describe exactly what you mean by "cranks two or three times". Are you talking about cranking for normal length of time (less than 2 seconds) then shutting off immediately? Then you trying again 2 or more times? Or cranking for longer than normal (>3 seconds)? Or is the engine only rotating 2 or 3 times when you turn the key to start?
Hi DrX,
I mean, normal crank time and shut off immediately, It seems engine is rotating 2 or three times.
Thank you. Normal crank time, engine catch/ignition, and immediate shut-off/stall is indicative of DAS failure. No LED blink with key in position 1 confirms it.

The fact that the problem is intermittent means your DAS ring & module is faulty. Replace it before it becomes permanent and bricks your key. Sometimes it malfunctions at low temperature and low voltage. (It's also called the transponder coil and immobilizer control module.)

New or used will do. If used, try to find one from a facelifted ML (2002+) that were fitted with better versions that don't fail when cold.

Also, buy a spare key from the dealer for $40.
Thank you,
I am going first with DAS ring & module because when it starts run great and sometimes I drive it for 280 miles.
Anyone have any pictures/part number or DYI? Do I need dealer to reprogram it? I have both keys why should I get a spare?
There's a link in this post to the part number. Pics are 2 posts above it.

Doesn't need programming.

You left out the part where you tried your spare key before you had it towed home from the shops.
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