I know there is alot on this problem but I yet to figure out mine . I have a 2002 4.6 supercrew 4x4 . Driving on thruway and it died . The power stayed on but truck died . Check engine light came on , abs came on , theft was blinking , odometer flat lined , no crank at all. I thought a smelt small burning smell but not sure.anyways I switched pcm . Nothing changed . Changed all relays and checked all fused . No change. The gauges flatline when I turn key to on and the check engine and abs light arent on but after ten minutes the gas and battery gauge cone up aND light camE on. But when I try to turn key agian everything flat lines agian. Odometer stays flat lines across it . And lights go back off. Tried hooking computer up to it when lights are on and it can't connect. Iv read alot . And most come baCk to pcm . I haven't tried cleaning grounds but I am tomorrow. Also I seen ppl say separate trans pcm might be a problem. Any tips on what to try next would be appreciated. Truck ran like a top . 230xxx miles . Fluids were good and everything worked so Im stumped. Grounds and transmission pcm are my next try but alot of these other threads I read there trucks cranked over . My won't . It doesn't even click. I jumped the soliniod and that turned the engine over so the starter is fine and the ground there is fine. Thanks in advance

 

Why did you replace the PCM? You know it won't work unless it's programmed to your VIN and keys. There is no separate TCM with a 4R70W. Put the original one back in and get your battery load tested.

From another member:

 

I wasn't sure if it did need to be programmed . I was 3 hours from home . The person I had come tow me grabbed the pcm from a parts truck I had at my house . I figured it was worth a try. But Ill thro the original one back in and go from there. I'm use to the older vehicles u can do that with. Thanks

 

- Don't know if you've solved your problem yet or not - but, I had the same thing - on freeway, 65+ mph, in a '99 f150 4.2 - thing just died - same instrument cluster symptoms, etc.

long and short - and it took three days to figure it out -

called wife - she took me to an auto parts store - bought and installed new battery - truck started right up, went home. next couple of days fine, then third day I'm noticing amp gauge falling to discharge side - great. get to work, got to auto parts store at lunch, buy new alternator - install in parking before going home. right away amp gauge shows positive charging happening.

Diagnosis: on way home when truck died at 65mph, it was because alt died - then battery took over until it drained and died - then truck died. New battery only lasted running truck (because alt wasn't) for a couple of days. Been driving 46 years, and doing my own repairs as long - should have recognized what was happening right off. But that was my problem; dying alternator took out the battery - you might want to check both. BTW - that was over 8 months ago - truck's been running fine since - 300k + miles, all OEM drive train, original owner . . . .

 

It ended up being fuse number 111 ignition switch feed 40. U can't hardly see that the fuse is blown. Just a hair line burn out in it . Anyways put a new one in . Started up . And I can hear a arch coming from engine compartment. So going to wait till tonight and pinpoint it in the dark.

 

Fuses have to be tested with a meter, you can't just look at the new style fuses like you used to with the glass fuses.

 

I done the same thing changed the computer and now it runs and misses with no power would I need to get the ignition from the same vehicle I got the computer from pllz help

 

Yes or have the original key programmed to the new/used computer... good luck... GB