P0122 code on A 2007 Dodge Ram 1500 5.7L Hemi

why are you changing all these parts? Is the truck STOCK no aftermarket BS? all is as delivered in 2007. OK you have ETC - elec throttle - the THROTTLE control warning light is on? you have a scanner showing live data ? F the key on off trick. To start what is the referance voltage?

Checking the voltage on the plug for the throttle body I have no voltage on pin 2 (F855). I have checked continuity to ALL wiring but no voltage out of the PCM for the throttle body. The PCM is brand new and just installed. My question does the Discover more Ram Pickup Fuel Engine Integrated Power Control Module (fuse box) have anything to do with the voltage to the throttle body unit? I can't locate a wiring diagram for this particular truck (2007 Dodge Ram 1500 with the 5.7L Hemi engine). Any help with locating a wiring diagram would be appreciated. In answer to your question why am I replacing all of these parts? I use this vehicle (or at least DID) to go way south in Mexico on trips. Eleven year old electronics make me nervous. Haven't won the lottery so no new truck on the horizon.

search this link - be sure to be looking at wiring http://www.bbbind.com/free-tsb/

What were the old codes that led to the ecm and pcm replacement? Are these parts brand new oem, and professionally programmed to the vehicle? If it doesn't start, you need to determine which elements are missing such as spark, fuel pressure, injector pulse, compression etc.

I can't remember the exact old codes that the ECM was putting out but it included camshaft sensor, crankshaft sensor, throttle control assembly, misfire on ALL cylinders, etc. As I worked through the codes I replaced the ECM, crankshaft sensor, camshaft sensor, throttle body assembly, accelerator pedal. I've checked the voltage to the ECM, etc. I still have no voltage to the (or from) acelerator pedal. I can't find a wiring schematic for the truck (2007 Dodge Ram 1500 5.7L Hemi, 4 X 4. Compression good on all cylinders (new spark plugs as well). Still not getting any fire to the plugs but I am assuming due to the code being generated. The only code now is the P0122 code. I replaced the TIPM (fuse box) as well but did not fix the problem. If I could find a link to the wiring diagram I could hopefully isolate the problem. The harness looks great (no fraying, etc. anywhere on the truck). Anyone out there have a link I can check for the wiring schematic?? Thanks again. Sorry for the delay in getting back but seldom home to check email. Direct cell is Four oh Five three 2 eight four three zero nine just in case the guru's out there want to give me a shout. Secondary reason for replacing electrical parts is anal retention on my part having worked on jets for almost forty years.........."If it ain't broke fix it anyway. It's your A** up there".

Just reviewed all of the associated wiring diagrams and still can't determine if the accelerator pedal input goes through the TIPM.

I would think that you should be able to start it without the app sensor even plugged in. I would think there would only be no throttle response. Do you still have the old pcm? Are you not getting 12volts to the ignition coils during cranking, or no grounding from the pcm drivers?

I do still have the old PCM. Using the old or new PCM does not change the P0122 code showing low voltage to the accelerator pedal. Disconnecting the battery or grounding the negative lead from the battery to the positive lead from the battery (to drain the system of all electrical) does not change the code. When it throws the P0122 code the engine dies and will not start. Interestingly if I leave the truck sitting for a few days (with battery connected) it will (sometimes) start, run at idle for a while, then die when it throws the code. This morning it started after cranking for about 5 seconds (prior to problems it would start immediately). When I advanced the accelerator pedal to around 2000 RPM's it would surge up and down about 200 to 300 RPM's. It did this at 2000 RPM and 3000 RPM. The engine would idle very smoothly. Then it again threw the dreaded P0122 code and died. No start now. I have checked continuity on every single wire I can get to with no indication of a broken wire. I'm not sure where to search now......... Appreciate the input!

At the app sensor there are 2 seperate 5v ref wires. 1 is pk with ylw tracer and goes to pin 29 at connector 2 of pcm. The other is ylw with pnk tracer and it goes to pin 27 at connector 1 of pcm. The TPS sensors only have a single 5volt ref which is also the pnk/ylw wire circuit from pcm. There is a splice for pnk/ylw circuit in the pcm harness at the right rear of engine bay. I once had an intermittant open in that circuit one time near the firewall. The harness was stretched behind the transmission dipstick tube, when it should have been routed in front of it. The 5v @ the tbi unit that is apparently missing, needs to be checked at the pcm. Note if the circuit is shorted somewhere it may read 0v. You may need to create an open to see if the PCM actually is producing the 5v. I believe the MAP sensor also shares this 5v circuit along with a couple other sensors that I am not sure of at the moment.

My wiring harness is, indeed, routed behind the tranny dipstick. I'll check both ref wires on the app sensor this morning. Your input makes more sense than the direction I have been searching so I'm eager to check it out. Appreciate the input! Keeping my fingers crossed that this is the culprit. I'll respond as soon as I get the opportunity to check it out.

I am having the same issue you had/are having... have you figured anything out? My SIL is a dodge mechanic and we went through the 5v stuff and found it was the crank positioning sensor. the P0122 covers a lot of sensors so deduction was the key, so I thought.. been a week and while driving down the road, I hit a bump and the truck went dead. Would not crank.. called a tow truck, they towed me home.. got it off the rollback and it started right up like there was no tomorrow.. wonder if im loosing a ground somewhere? any more suggestions? thanks

Ok.. This is what I feel is the culprit. Was doing a lot of reading and I found that there is a group of wires "6" that run on the passenger front of the motor, right above the oil filter. 2 are for the knock sensor, 1 is for the oil pressure sending unit, and the remaining 3 are for the crank positioning sensor. I found a chaffed wire, at the front of the engine block, going to the CPS, I replaced all 3 wires, just because I could and re-wrapped them better and I have had no issues since then, knock on wood...