[Sandib210]

hi all,
hoping someone has run into this before and can give me a hand. Today I noticed when I turned over my 07 diesel Grand Cherokee the check engine light came on (and stays on) and the glow plug light comes on for about 3 seconds or so.
Any clue as to what would trigger this??

[Sandib210]

I'll add that when I retrieve the code by turning the ignition on and of 3 times quickly I get "service 4wd system"

[NDSU_Bison]

You probably need to have one of the glow plugs replaced. I had the same thing happen to me although they had to replace the glow plug control module when replacing the plug listed in the fault code didn't help. It's probably not a big deal in the summer like it would be on a nice cold Saskatchewan winter day.

[TurboDiesel]

Originally Posted by Sandib210

I'll add that when I retrieve the code by turning the ignition on and of 3 times quickly I get "service 4wd system"

i hope ur not litterally turning the truck on then off....

[quicksilverado]

Originally Posted by TurboDiesel

i hope ur not litterally turning the truck on then off....

You turn just the ignition switch on and off 3 times. You don't actually start the engine. You can do this with most vehicles and then count the sequence of flashing lights to get the trouble code.

[Sandib210]

Originally Posted by quicksilverado

You turn just the ignition switch on and off 3 times. You don't actually start the engine. You can do this with most vehicles and then count the sequence of flashing lights to get the trouble code.

yes, that's what I meant. . . some call it the key dance?? When I do that I get 'service 4wd system', but no other codes.
I changed the battery today, and now the glow plug light no longer comes back on. Just the check engine light comes on.

[TurboDiesel]

yea i know how to do it...just wasnt sure if the OP did lol glad we got that cleared up atleast

[Sandib210]

I could still use a hand with this problem. I've installed a new battery, I'm getting the battery light on at start up until I rev it up a bit, and I still have the check engine light on. Could this be a belt? bad alternator? any ideas??? sometimes the glow plug light also comes on for a second or two immediately after start up.

[jiggadog]

have you pulled the codes? as mentioned, you likely need to replace a glow plug. you may have an alternator issue if the battery light is coming on.

[Sandib210]

Maybe I should buy a code reader? Key dance gives me DTC report - ---- most of the time and occasionally "service 4wd system"

[va7cid]

if you are still trying to fix this, it's likely a bad glow plug. I would suggest to get an OBD reader that will give you the correct code. It will come in handy with an newer vehicle especially with us CRD owners.

Same thing happen to mine that started with a bad #5 glow plug, for me it's the on in the middle at the left engine side or the driver side. Replaced it with a Bosch Glow Plug for $35 at VAP (dealer wants $80 each) and 3-4 weeks later the engine light came on again with a glow plug module code. I had no choice but to replace it as it was a dealer item at $350 and erased the code and it has been fine since.

Love the torque with this engine but we must deal with the minor hick up as they age, good luck with it