2003 5.4L LIGHTNING SVT. NEW OEM PCM no communication with pcm and odometer has lines across it cluster takes like 3-5 minutes to power up. engine not firing need help!!!!!!!!!

 

You swapped the PCM ?

Did you program the new PCM / HEC pairing ?

The PCM and the HEC communicate with each other over the multi - comm network.

Think the HEC has the PCM ID stored in it, but I could have it the other way around ( don't think so ?? ).
The PCM ID in the HEC needs to be erased, so it can learn the new one.

You need a WDS or IDS to erase the PCM ID in the HEC ( unless I have it backwards ). Been some time since this has come up.

Maybe try a search from the top with PCM ID or HEC ID and see what threads come up ??

What do you mean by :

 

I can't communicate with my snap on scanner now fuel pump runs all the time

 

What is the hec??????

 

What is the hec?????? And why would it not display the millege all i see is -------- ????

 

HEC - Hybrid Electronic Cluster

You need to get this to a place that has a WDS or IDS, you swapped out a part, that is not end user swappable.

Like I said above, the truck is not programmed for the new PCM. It does not complete the self tests over the multi comm network.

If you put the old PCM back in, it might work fine.

Start with getting the new PCM working with the HEC prior to trying to use a DTC scanner on it.

The other question becomes, do you have the correct PCM for your as built data in your truck.

 

I order the ecm by vin# and checked part # from ford i have had no luck!! The 1st ecm from ford came with water damage!!! Also the old ecm had a sct tuner program in it. That ecm dont work either. I dont see 12volts to turn on ecm with key on. Grounds check ok! I shipped the truck to ford dealer they had it for 1 1/2 weeks they cant find the problem!!! All they say is they can't communicate with the (can bus) and the fuel pump is on all the time with key on. Engine is new built dealer left they key on and filled the engine with fuel!!!!!! Fuel comming out of the trottle body!!~!!!

 

The old PCM, a Ford dealer could reflash, and overwrite the SCT tune on it ( that is the #1 reason to return a truck to stock when taking it to the dealer, no surprises ).

The PCM if ordered by Vin #, should be the correct one ???

If you do not have voltage with the Key in the run position, have you checked the PCM fuses, and the PCM power relay fuse ?

 

I dnt get why is there a 3-5 minutes delay after ignition is on before the relay powers up ??

 

Start with getting the HEC - PCM pairing correct.
Without this, you can do a bunch of testing for nothing.

Did you do the search yet ?

Found a few threads, one with similar symptoms

https://www.f150online.com/forums/ch...tion-help.html

PCM_ID info ( it is the HEC that stores the PCM_ID )

https://www.f150online.com/forums/li...nt-merged.html

https://www.f150online.com/forums/li...terminals.html