I have a 1999 2500 Cummins 24v that keeps getting the p0122 tps low voltage code on every tps the first time I changed it, it lasted a week then got another dead pedal so I replaced it again thinking I got a faulty tps and the new one last 2 days and I got the p0122 code again and the truck surges off and on. Ive did the reset procedure and it idles fine. Any ideas to what could be causing me to keep getting these problems thanks.

Welcome to the family...

 

First off did you test for excessive AC noise from the alternator? Grab a digital volt meter and test right at the alternator BATT terminal it should measure less than 0.1 AC volts.

 

Second did you do the diagnostics for the error code?

http://articles.mopar1973man.com/2nd-generation-24v-dodge-cummins/59-obdii-error-codes/151-p0122-apps-sensor-signal-voltage-too-low

Thanks for the reply and as of right now I have red the diagnostics to check the continuity from pin #5 on my apps to pin #31 on my ecm but have not had the chance to check it yet. It seems really hard to get down to the ecm to get a good look at what I'm doing.

Pull the fuel filter out of the way. Then there is a Allen screw holding the plug into the ECM.

Thanks I will try and check that soon and let you know what I find

i was able to work on my truck today and i have no voltage between my apps connector and the block what does this mean.

i was able to work on my truck today and i have no voltage between my apps connector and the block what does this mean.

the resistance between terminal 5 on apps and terminal 31 on ecm connector 1.2 ohms

0 to 5 ohms is normal.

 

Now probe from one side to ground all connection should show infinite ohms in others words there is no wires shorted to ground. Make sure to have both ends (ECM and APPS) unhooked.

Step 7 in the diagnostics state that if the resistance is 5 ohms or less, replace ecm. My reading was 1.2 ohms. Am I understanding that correctly? Thanks again fir your help

Did I miss something?

 

Testing

1. Turn ignition on with engine off. Using DRBIII® scan tool, check for ECM and PCM DTCs. Determine if DTC is set by ECM or PCM. If DTC is set by ECM, go to next step. If DTC is not set by ECM, go to step 7 .

2. Turn ignition off. Disconnect APPS sensor harness connector. APPS is located on bracket, just above fuel injection pump. Turn ignition on with engine off. Using DVOM, measure voltage between cylinder block (ground) and terminal No. 5 (Dark Blue/White wire) on APPS harness connector. If voltage is greater than 4.5 volts, go to next step. If voltage is 4.5 volts or less, go to step 6 .

3. Turn ignition off. Ensure APPS harness connector is still disconnected. Check for continuity between terminal No. 4 (Black/Yellow wire) and terminal No. 5 (Dark Blue/White wire) on APPS harness connector. If continuity does not exist, go to next step. If continuity exists, repair short between Dark Blue/White and Black/Yellow wires. The Black/Yellow wire is the sensor ground circuit.

4. Ensure APPS harness connector is still disconnected. Disconnect ECM harness connector. ECM is located on driver's side of engine, just in front of fuel transfer pump and contains a 50-pin connector. Check for continuity between terminal No. 4 (Black/Yellow wire) and terminal No. 3 (Light Blue/Black wire) on APPS harness connector. If continuity does not exist, go to next step. If continuity exists, repair short between Black/Yellow and Light Blue/Black wires.

5. Ensure APPS and ECM connectors are still disconnected. Check for continuity between ground and terminal No. 5 (Dark Blue/White wire) on APPS harness connector. If continuity does not exist, go to next step. If continuity exists, repair short to ground in Dark Blue/White wire.

6. Turn ignition off. Ensure APPS connector is still disconnected. Disconnect ECM harness connector. ECM is located on driver's side of engine, just in front of fuel transfer pump and contains a 50-pin connector. Check Dark Blue/White wire for continuity between terminal No. 5 on APPS harness connector and terminal No. 31 on ECM harness connector. If continuity does not exist, repair open in Dark Blue/White wire. If continuity exists, replace and program the ECM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article.

7. Turn ignition off. Disconnect PCM harness connectors. PCM is located at passenger's side rear corner of engine compartment. Check for continuity between ground and terminal A23 (Orange/Dark Blue wire) on PCM harness connector (APPS circuit). If continuity does not exist, go to step 9 . If continuity exists, go to next step.

8. Disconnect ECM harness connector. ECM is located on driver's side of engine, just in front of fuel transfer pump and contains a 50-pin connector. Check for continuity between ground and terminal A23 (Orange/Dark Blue wire) on PCM harness connector (APPS circuit). If continuity does not exist, test is complete. If continuity exists, repair short to ground in Orange/Dark Blue wire. 9. Ensure PCM harness connectors are still disconnected. Disconnect ECM connector. ECM is located on driver's side of engine, just in front of fuel transfer pump and contains a 50-pin connector. Check for circuit). If continuity does not exist, go to next step. If continuity exists, repair short to ground in Orange/Dark Blue wire.

10. Check Orange/Dark Blue wire for continuity between terminal No. 5 on APPS harness connector and terminal No. 31 on ECM harness connector. If continuity does not exist, repair open in Orange/Dark Blue wire. If continuity exists, go to next step.

11. Reconnect ECM harness connector. Ensure PCM harness connectors are still disconnected. Turn ignition on with engine off. Using DVOM, measure voltage between ground and terminal A23 (Orange/Dark Blue wire) on PCM harness connector (APPS circuit). If voltage is greater than 0.4 volt, test is complete. If voltage is 0.4 volt or less, go to next step.

12. Turn ignition off. Disconnect APPS harness connector. Check for continuity between ground and terminal A23 (Orange/Dark Blue wire) on PCM harness connector (APPS circuit). If continuity does not exist, replace APPS. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. If continuity exists, replace and program the ECM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article.

 

 

 

 

 

 

Ok. I followed the link for 2nd gen 24v and went to troubleshooting P0122. The procedure you posted is a little diferent. I will follow these when I can and advise. Thanks

the last 2 apps sensor i have bought for my truck did not cone with a tag i know that you are supposed to set it lower than what The tag says but how do tell what mine is supposed to be set at.

Hello All,

 

I am fairly new to this site but I have received a lot of help from other members.  I have a 2001 Ram 2500 with the 24v Cummings.  I have had the dead pedal issue twice with this truck.  The first round, I ended up going through and removing, cleaning and greasing all of the ground wires I could find under the hood.  One of them was bad and this fixed the issue.  This last go-round with the dead pedal, the problem was very intermittent.  I was getting numerous codes including 1690, 1693, 0122.   I adjusted the voltage at the APPS.  It was low when I started.  That took care of the 0122 code.  I also spoke with a tech at out local dodge dealer.  He gave me a factory wiring fix that by-passed the ECM.  You add a wire at the PCM, and wire it directly to the APPS and you also add another ground directly to the battery.  This repair was for the erratic shift issue.  I can post the diagram if need be.  While having the dead pedal issue the transmission was shifting all of the time,  In and out of overdrive.  Unfortunately this did not fix the dead pedal issue or the shifting issue.  The truck would idle fine most of the time, but every so often it would "hiccup" if you will.  During one of the "hiccups" I noticed a little puff of smoke coming from the solenoid on the side of the fuel filter.  As it turns out, the culprit of all of my issues was the solenoid for the fuel heater in the fuel filter.  There were some bare wires and it was fried.  I replaced the solenoid as well as the actual fuel heater in the filter and the truck ran fine.  Cost was around $240.  I know the headaches of the dead pedal issue and I hope this helps.  

First off the only ground you need to worry about is the passenger side ground cable. That is the master ground for the ECM, PCM and VP44. The rest of the body grounds are all secondary circuits like lights ,horn, etc.

 

Never adjust the voltage to the tag value. Always leave it BELOW that value by at least 0.1 volts and use the set screws. If the APPS doesn't have a tag it most likely a Timbo's APPS and there is no voltage to set.

 

Shift issues is a alternator problem. Do not add grounds or wires to the PCM they are NOT needed.

 

http://articles.mopar1973man.com/2nd-generation-24v-dodge-cummins/26-engine-systems/37-apps-sensor-voltage-adjustment

 

http://articles.mopar1973man.com/2nd-generation-24v-dodge-cummins/26-engine-systems/39-timbos-apps-installing

 

http://articles.mopar1973man.com/2nd-generation-24v-dodge-cummins/28-transmission-systems/260-torque-converter-lock-unlock-issues

Kudos to Mike Wingert for the above post. Thanks Mike for posting that. Very often doing the inexpensive steps first will find the problem. Often what is thought to be a bad part is part of the symptom not the problem.

 

This is the beef I have with my doctor, he likes to prescribe things for eliminating the symptoms

Like Mike's post above the dealer and shop like to modify a good electrical system because of a issue. You got to ask yourself the question how come the truck ran 10-12 years now without this mods and why does it need it now? This why I tell people to pull that stuff back out and see the problem is still there and masked by the cheap band-aid. Kind of like you JAG1 you doctor covers over the problem will a pill. Why not fix the actual problem?

My doc is a total pill .... here take this   and swallow that  he says... and I'm going  

 

One says I have a heart mirmer, another says no there's nothing there. Another says I have to take an expensive 2,000 dollar scan when another says just a simple ultrasound will work instead. Sheesh it's like going to a car dealer.

 

So far I've found eating raisins, carrots, good salad, exercise, and avoiding food additives helps loads when all I need is a way to stop eating doughnuts.

 

Sorry about getting off topic here