Alright, I've been fighting this battle for almost a week now. My 2004 duramax won't start, it won't crank over, I have no glow plug light and no check engine, I have power in the cab, all my lights on the dash light up and my gauges read, I also have headlights, the only indicators on the dash that come on are the battery light and the security light. This all started last Friday when my alternator went out on me. I bought one after work that same day and swapped them that night, I started my truck to see if it would charge but I still had the same no charge issue, so the next morning I took the new and old alternator and went to the local parts store and had them tested, the new one was good, so I go Hoke and put it back in and I go to start my truck and I've got nothing, won't crank no gp light and no CE light. I've checked fuses I've checked power at them, I had a scanner hooked up and was given a p1621 error code saying the long term memory module needed to be reprogrammed. So I pulled the ecm to have it tested and was told that it tested good on the bench, I'm at a loss of words right now, I have no idea what it could possibly be, I'm very disappointed with this truck so far. If anyone has any sense of direction please I'm all ears.
need direction
- Thread starter ryanelwood
- Start date
I had a 05 that did this a few years ago and I had to replace it with a new ecm. First, try having the dealer flash an updated TIS file into it though.
Make sure all your grounds are good also. Should have like four or five between both sides of the engine block near the front just in front of the motor mount. THere is one on the back side of the driver head and then another that goes to the frame just under the radiator core support on the driver side . Like 6 or 7 to check. If they are broke, loose or corroded they will cause quite a few strange issues.
I'm gonna hopefully try and check all the grounds tonight to see if that's what's causing this. Does the dealer need the truck to flash it or can I bring the ecm to them?
Alright here's an update, swapped ecm out of a truck that was just running, still same issue, no crank, no check engine light, no glow plug light. Therefore I have eliminated the ecm. I have no blown fuses, I've checked them over a dozen times myself and had two others check also just to make sure I didn't miss anything. I have power to all the fuses that I am suppose to have power to EXCEPT for the IGN 3 on the instrument fuse panel, I'm not sure if that is suppose to have power when key is on. One other thing I did notice is that my seatbelt lights are VERY dim and sometimes don't even come on at all. Any input you guys have is greatly appreciated!
Well, I guess the dealer got it figured out, apparently the entire fuse box underneath the hood needs to be replaced...not sure why or how but if it gets my truck running I don't have much to complain about. Will have to speak with service manager to get an explanation of why.