2007 Ram 5.7 wont start after stock tune restore

[drnico]

So long story short, I recently got long tube headers (to add to catback exhaust, throttle body spacer, CAI) and was throwing a 'running too lean' check engine light. Wanted to restore back to stock tune and see if that helped, and eventually get a custom tune done.

So with difficulty, I did manage to restore back to a stock tune, and I thought everything went fine, no error codes or programs crashing. Had to do this anyways before updating my diablosport predator. Did manage to update to u7137-9r13 after restoring to stock tune.

However, I just tried to start my truck, and it wont go. Wont turn over at all. I can get power to it when I turn on the ignition, but as soon as I turn the key as far as it will go to try to start the truck, the power seems to cut out? My radio, headlights, interior lights etc go off, and then come back on when I stop turning the key.

To make everything worse, my 7137 now cant communicate with my pcm, so I can't even try putting on a performance tune to see if that fixes it.

Besides going to the dealership and getting them to reset my pcm, is there anything I can do?

[Mike_Levy]

Sounds like the battery may be weak. Can you jump it?

Whatever you do, don't go to the dealer. They will tell you that the PCM is fried. IT IS NOT. If it won't jump start, you're out of luck untiil Monday, but call tech support Monday morning and they'll get it going for you.

[drnico]

I tried yeah, I have a Trojan battery I use for an elec trolling motor that I keep charged/tended 24/7, and it didnt make a diff when I hooked it up to jump. battery gauge is fine as well. Maybe I'll try leaving them connected for a while...

Darn, was supposed to get bumpers installed monday morning

[bhrodeoaz]

well---first off mine did the same thing when i programmed mine i have an 05 ram hemi--- it was a bad battery--- swapped batteries ran for about an hour before i found out it was a bad alternator. SO with that said i would take the batt and have it tested at autozone or oriley to see if your batt is bad. And as to jumping when your jumping batteries your drawing power from a battery to maintain power in another---- with out a charging source the effort is useless--- but testing the battery is free.

[drnico]

K will get it tested... just don't understand why all the sudden (if it is the battery) it gave out? I just came back from a 3,000 km camping trip and it held up just fine. Had the ignition on for all of 10-20 mins while I was changing the tune.

[drnico]

Also, my radio, headlights, dash lights etc. all work to what appears to be full power. And my 7137 says 'unable to communicate with PCM'...

[bhrodeoaz]

but what you have to realize is the predator requires a certian amount of voltage in order to remain running to communicate with your PCM/TCM--- if your batt is below that threshold it will not communicate--- same power requirements are also required when you update the unit to the latest CROM update

[bhrodeoaz]

also check the OBD II connection if the needles on the predator cable are bent/broken it wont hook up=== seems far fetched but a plausible cause--- try to eliminate problems that you can do your self at home first

[Mike_Levy]

The Predator requires 12V. The accessories will normally run with as little as 9.6V.

Stupid question, but you do have the key in the ON position when it can't communicate, right?

[drnico]

ahh ok, I understand. checked the prongs, all good. yeah key is in on position when it can't communicate... so looks like I'll go with the battery for now and update you guys.

thanks for all the help so far, much appreciated!

[typan]

what I would do before going to have the battery tested is do it yourself, get yourself a digital multimeter & place the probes on the battery posts in the trunk & switch on to the accessories position and have someone looking at the meter to see what voltage is at the battery should be about >11 volts next try to start the car & once again get someone to look at the meter, if the voltage at the battery is below 9 volts then your battery requires charging or it's fucked simple as that.

[drnico]

Well I dont have a digital multimeter, but I have an intelligent battery charger that displays volts and amps. When I connected it, volts were 12.8, and when trying to start, dropped to 12.6 (assuming because the custom HID headlights I have which are hooked up to the ignition go off when trying to start)... so everything seems ok with the battery in that sense... I left a different trickle charger on for about 3 hours and tried to start it after - no difference. Still wont even turn over. I have the other intelligent charger on now, so I'll leave that on for a few hours and give it another go.

[typan]

Well it looks like the battery is fine, it looks like it may be in the starting circuit I'll be checking the fuses, starter relay & starter motor etc. any error light on the dash?

[drnico]

Left the charger on all night, it read 'full' in the morning, tried to start - nothing.

I checked all the fuses before, no problems there...

Youtubing/googling how to check my starter relay and motor, but I doubt one of those just gave out, like the battery... for some reason I think its some software component that got screwed up in the PCM when putting back on the stock tune

[drnico]

Called diablosport and looks like I have to get the PCM reflashed