APPS low voltage p0122

[Mopar1973Man]

Another answer... Now notice there is such a wide range of APPS voltage tags seen out there and Wells APPS stating to get in between 0.5 to 0.6 volts. Why? That's easy. When your dealing with electronics resistors and such are not exact in value its always in tolerance of 5% or 10% or may 20% so now the possible voltage toggle position could be any where between X to Y because one resistor could of been +2.5% and the other could of been -6.9% off the mark.

 

2 minutes ago, leathermaneod said:

Makes me wonder if mine would throw a code if I took it to WOT?

 

I doubt it... If it would you could just turn the key ON (engine OFF) and press the pedal to the floor it would trip code if out of range.

 

Edited June 20, 2016 by Mopar1973Man

[leathermaneod]

Well I'm very thankful to you for sharing all your knowledge on this stuff! I'm always glad to learn and understand new things about these trucks. 

4 minutes ago, Mopar1973Man said:

 

I doubt it... If it would you could just turn the key ON (engine OFF) and press the pedal to the floor it would trip code if out of range.

 

Funny I was thinking maybe this would be the case right before you replied. I'll have to try it when I get it up and running again. I was planning to do the apps relearn anyway

[Mopar1973Man]

Another tidbit... About APPS relearn why is it that we have to do it? That's because again when your dealing with electronic device ECM vs. the APPS regardless of manufacture the APPS relearn only sets the lo and hi limit of the current APPS sensor. It just when you do a APPS reset your wiping out the memory on the ECM and the first key on your cycling from lo to hi volt range and turning the key off. This sets the limit of range for the ECM and it knows this is normal range now. So the ECM knows X volts is 0% throttle and Y volts is 100% or WOT.

Edited June 20, 2016 by Mopar1973Man

[notlimah]

So in the case of timbos apps, when you re-learn positions you're really doing that for the ECM and not the timbo?

[Frankstein]

Thanks for comments and knowledge guys!!!!   I checked my voltage yesterday. I was around in .410 range.  maybe too low??  I relearn the APPS adn drive it .  On my edge I got 2-3-4 % throttle at idle..   I'll try to put the voltage in .5 to .6  range and relearn it!!      Maybe gonna go with a Timbo next time.

[leathermaneod]

 

6 hours ago, notlimah said:

So in the case of timbos apps, when you re-learn positions you're really doing that for the ECM and not the timbo?

If I'm not mistaken, you are doing the relearn for the ECM wether you have a Timbo or any other APPS. Either way you are telling the ECM what the new maximum and minimum voltages are.

41 minutes ago, Frankstein said:

Thanks for comments and knowledge guys!!!!   I checked my voltage yesterday. I was around in .410 range.  maybe too low??  I relearn the APPS adn drive it .  On my edge I got 2-3-4 % throttle at idle..   I'll try to put the voltage in .5 to .6  range and relearn it!!      Maybe gonna go with a Timbo next time.

 

I could be wrong so hopefully Mike will chime in again and clear things up, but I would say if your set in the .4 range and the code is saying voltage too low, but the edge is saying your throttling, then the sensor is junk because the IVS is thinking your throttling when it should be seeing idling. I don't think raising your voltage is going to help because that will just push you from 2-4% to a higher percentage....like I said though, let's see what Mike says. I'm not totally sure if I understand all this correctly yet lol At the same time I don't think you will hurt anything by adjusting your voltage higher and seeing what happens, but it sounds to me like your in need of a Timbo APPS....

[Mopar1973Man]

1 hour ago, Frankstein said:

I checked my voltage yesterday. I was around in .410 range.  maybe too low??

 

Timbo do not adjust for voltage! Leave it alone...

 

Stock APPS I would leave i alone.

 

Wells APPS I would adjust it.

 

As for the 2-4% TPS number it could be a module or programmer messing with the signal. Try removing them and see if it remains. Here shortly it might toss a P0121 code.

 

If APPS reset gives relief but reoccurs again thee you dealing with an alternator issues with excessive AC noise that is messing with the ECM now.

 

Edited June 20, 2016 by Mopar1973Man

[Frankstein]

Thanks Mike and leathermanoed!    Mike in my truck I have the Airtex APPS   # 5S5352 . This morning I've set the voltage at .515 around. Like instruction come with APPS  between .5 to .6V.  I relearn and drive the truck today.   I check for code,no code.  sometime it has 3-4% apps on edge. drive the truck, stop the engine and restart....   on my edge sometimes apps % is ok 0-1% idling.      Mike I check for AC at alternator like you did in your video and seems ok but maybe my voltmeter is not enough good. Will try to check it with a good ones..

 

Thanksd again  for help!!     

[Mopar1973Man]

@Frankstein If your APPS wears out would you mine sending it too me... I'll cut it open and show the guts too.

[Frankstein]

Yes Mike!! depend on shipping cost, I'm from Quebec,Canada.....     I'll drive the truck and check the electronic for bad ground or anything else.   If I have to buy a new APPS maybe a Timbo    in the futur,  I'll  write you about shipping my APPS 

[Frankstein]

HI, the p0122 just came back!!  Do you think its my APPS or I need to check something else??

[Mopar1973Man]

Do the diagnostic of the P0122 before just going out to buy an APPS.

[dripley]

I agree with Mike on this one. My engine has been surging for the past 2 years with several low and high voltage codes. Doing the diagnostics it has always pointed to the APPS as the problem. But replacing has never worked. Pretty sure I have a short somewhere. Maybe not the same thing but $180 to find out is a little pricey. That is why I have two APPS now.

[Frankstein]

For sure!!  I'll try diagnostic first before spending money for maybe not the problem..  I maybe thinking of electrical problem cause some weird things happens. I'll try to find when have time and let you know guys.  Thanks!!!!

[Frankstein]

Hi guys some update!!!!  it was hot here for about 2-3 weeks,so during morning startup the wait to start light doesn't came on and my apps % was good 0 to 1% nothing more. 

1. One morning it was little colder, when I start the truck I have the wait to start .   So when the truck running and air intake heat cycling the Apps goes from 3-4% to 0%.....  After cycle it stays at 3-4% during driving.  after some driving and start- stop engine the apps return to 0-1%.

I don't understand what's the trouble.  like a trouble with air intake heater and ECM?????   the grounds are clean!

 

[Mopar1973Man]

AC noise test? 

 

[Frankstein]

I tried with my multimeter but its not a good quality. I need to buy a good one!!  

[Royal Squire]

I have occasionally experienced a dead pedal and cel with p0122 code ever since I bought this truck, so today I finally decided to order a timbo apps. Afraid it will quit completely out in the middle of nowhere.