Archived 04.5 cranks and won't start... lift pump cycles on and off

[AGervasio]

My 04.5 has been running great....parked it a few days ago ....went out to start and the lift pump cycles on and off repeatedly and cranks but won't start. Also code reader won't communicate with obd port nor will smarty programmer. Gauges don't respond with key on....fuel gauge reads empty and fuel light is on. Batteries are less than a year old and test strong....cleaneds posts...ck all grounds and fuses....disconnected fan clutch...no luck. Is my computer fried..

Ecm or pcm.....please help!

 

[Missouri Mule]

Seems strange that ecm and pcm would act up at same time. Were you working on any electrical components before you parked it or lighting around.










































Do you have tilt steering wheel on 2nd gen they were a problem. Pull connector of ecm and pcm and spray them down with contact cleaner (I buy crc drying stuff and lubricating. I use it on my back up light switch. Spray the lube one first let set for a few minutes then spray with the drying one ( I know the instructions are different on the can).

 

[AGervasio]

It's a third gen...and it's always garaged so I don't think it's moisture. Didn't know if anyone ever experienced this same sequence of events. I have never had electrical problems with this truck prior. In other forums people say it could be e cm or the pcm.....but not sure if it's that at all.

 

[cerberusiam]

There is no PCM, only the ECU on the side of the block. Might be worth pulling all the battery cables and tie the grounds together with jumper cables to discharge and reset the ECU. While your at it, pulling the ECU A&B connectors to look for corrosion and cleaning them would be next.

Also, check the OBD port and wiring to make sure it hasn't shorted or rubbed a wire somewhere. A shorted wired on the data bus will take everything down.

 

[AGervasio]

Thank you....i will try this next...so do I pull the positive battery cables and tie the negatives at the battery together with jumper cables?

 

[cerberusiam]

Remove all the cables from battery posts, tie the ground cable ends together.

 

[AGervasio]

Please excuse my ignorance....by tying them together that will automatically make the ecu reset? Thx for your help

 

[cerberusiam]

No, removing the power forces a drain of all the capacitors and wipes volatile code forcing and hard reset like CTRL-ALT-DEL.
The code is somewhat dynamic based on operating parameters and it will hold in memory some of those derived parameters.


Tying the grounds together just insures that a chassis ground is working if one is compromised. There are multiple grounds and theoretically it should not matter but sometimes it helps if there is a bad connection somewhere.

 

[AGervasio]

Ok I tried the ctrl alt delete method....no change....same condition exists....when I remove the ecu a and b connectors what should I clean them with?

 

[cerberusiam]

Spray electronics cleaner. Any sign of a corrosion trail on the ECU? If that doesn't work then could be power to the ECU, fuse for ECU, or it toasted the ECU.

 

[AGervasio]

No sign of corrosion....in fact everything was immaculate....can I remove the ecu and send it out to be bench tested somewhere?

 

[cerberusiam]

You would have to send it to a one of the ECU rebuilders\reconditioners to have that done. The results may not be good, like 3 times to get a working one, but if it is dead not much choice at this point. I am dreading it, corroded the fan control circuit pin off of mine and need a new ECU, need the truck. Not sure what is the lesser of 2 evils.

 

[AGervasio]

I use the truck for work so it sounds like I should just get one from the factory? But then it has to be installed and reflashed....and I'm assuming i lost my smarty s06 program....correct?

 

[cerberusiam]

Yeah, you will need to contact Bob and get an unlock for the Smarty if you have to get a new ECU. It is VIN locked now and not sure what will happen if you get back an ECU with a stock program, even if the VIN is correct. It just might let you go ahead and reload, never had to do that yet.


New ECU is $2400 and what ever the dealer is going to charge you to flash it. They will need the truck as they cannot bench flash anything. Reman ECU is $600-800, but, sometimes their QC has some questionable efficacy.

 

[AGervasio]

Thank u for all your time....is Bob someone from smarty that you know....if so can you send me his contact info please

 

[hcole]

Do you have trouble with rodents? Sounds like something happened to it while sitting like the can bus wires shorted together. I'd look for gnawed wires.

 

[cerberusiam]

Bob Wagner, he should have a user name on here if you want to try to message him.

You can try this also -- email address removed --.

 

[AGervasio]

Thank you for all your help again