Replace your 03/04 APPS sensor for less than $100 and 2 hours time.

[porambo]

***DISCLAIMER*** everything you do to your truck is your responsibility, I have no liability if you follow what I did to fix my truck. Take it to a professional if you do not feel comfortable doing it yourself after reading through completely. ***DISCLAIMER***

Backstory time. So the infamous red lightning bolt. I started getting it this winter intermittently and after a brief parts cannon approach of changing the throttle body and MAP sensor (new ‘Standard’ part had worse calibration than my OEM map sensor) yet the issues still remained I knew it was going to be interesting. My ground between the battery and engine block had a very poor connection so I cleaned up all the grounds and battery terminals. I highly recommend getting the android application torque or car scanner ELM (or an Autel unit or take it to someone who has a good scanner) to be able to get info from your truck otherwise this would be a lot more difficult if not impossible to troubleshoot especially as all of my issues gave no check engine lights to help diagnose. I had an intermittent cable TPS #2 between the throttle body that had several tenths of a second drop outs. ~11% is idle on my truck, 0% is an error. I ran a new cable straight from the throttle body up and over to the ECU to fix that. [tpsCableIntermittent]



The APPS (accelerator pedal position sensor) also had issues. It would drop out intermittently as well but only for very brief moments. [appsIntermittent]


I was going to replace the accelerator pedal position sensor with a OEM one but checking the prices its INSANE almost $2000 from advance auto and dodge isn’t making them anymore, and never originally built them as they’re a mercedes part, yet it seems that they aren’t being made by mercedes either even though they are typically very good about keeping parts around. So here is the work around.

Buy a mercedes CLK320 pedal sensor part number 0125423317. [0125423317] The problem with this sensor is it has 6 pins side by side and the wiring is different (more on that later). The dodge APPS sensor has 6 pins in a straight line, they won’t fit together. The way to get this sensor to work is to de pin the oem connector (you can always reverse this and put it back to stock if you want to) and use a different connector that will plug into the CLK320 sensor. The throttle body connector for a 2008-2010 jeep wrangler or dodge caravan will connect to the CLK320 sensor. That part number is 68018956AC. [68018956AC]





YOU'll NEED
10mm wrench/socket.
8mm socket
Something to de pin the connector, I bought a Harbor Freight test probe set for $4.
Phillips head bit or screwdriver
Torx T30 bit or screwdriver
APPS 0125423317
Connector 68018956AC
Optional: small needle nose pliers



CHANGING THE SENSOR

Unhook the battery ground cable.

8mm socket to take off the driver's fender liner (watch the cables that are attached to the liner).

Phillips head to pull down the APPS box [appsBox].


Unhook the 6 pin APPS connector, remove tape, pull back wire loom, and unlatch the pedal cable which pops right off [6pinApps].


Look at how the spring is set for pulling it back to no throttle, this is important for driving safety on reassembly. Remove the APPS, spring, and adapter bracket from the box by unscrewing the two torx T30 screws.

Unlock the connector [unlock6Pin].


Release the shell of the connector and pull off (mine broke as it was brittle) [releaseShell].


CAREFULLY depin the connector one wire at a time. You need theses locks to still function ideally. I’m not the best at explaining, watch some youtube videos. https://youtu.be/Vt_rAIKPlWA?t=927
If you’re color blind number the cables so we can keep the orientation. The #1 wire is furthest away from the alignment tab and closest to the release tab.
[depin6Pin]


Unlock the new connector by sliding the latch sideways and depin the connector. I didn’t have any luck locking the latch back with the dodge truck wires, you might have more luck but even if you cannot get the latch locked the pins will still lock in [unlatch6Pin].


Here is the pinout orientation for the new connector with the flat part on top and the curved section on bottom looking from the back of the connecter where the cables enter inside [pinoutFromBack].


Here is the service manual from the truck for the different pins [dodgeAppsPins].


Here is the mercedes TPS and pinouts [mercedesTps][mercedesTpsPins]




This is the translation from mercedes on the left and dodge on the right.

Pin 1 5V+ power - Wire 3 Pink with Yellow line
*Pin 2 5V+ power - Wire 2 Yellow with Pink line
Pin 3 TPS#2 return - Wire 4 Brown with Violet line
Pin 4 TPS#2 signal - Wire 1 White with Brown line
Pin 5 TPS#1 signal - Wire 5 Brown with White line
Pin 6 TPS#1 return - Wire 6 Brown with Yellow line

*mercedes says that pin 2 doesn't go anywhere inside the APPS but you can hook it up anyway, doesn't hurt.

If your pigtail/new connector came with weather insulation you can put them on the truck wires for protection.

Install the wires in the new connector based on the translation above. You can use the needle nose pliers to help seat them. They were a little of a struggle.

You can try and close the lock but mine didn't want to close as I think the wires are too big. They are still locked in.

Install the new APPS sensor with the bracket and spring in the APPS box.

Connect the APPS wiring to the apps sensor and attach pedal cable.

Attach APPS box under battery.

Attach battery ground.

Check your work by turning key to ‘on’ and see if the red lightning bolt goes away.

Fit finder liner.

Recalibrate APPS sensor. From the service manual.
(a) Connect negative battery cable to battery.
(b) Turn ignition switch ON, but do not crank
engine.
(c) Leave ignition switch ON for a minimum of
10 seconds. This will allow PCM to learn electrical
parameters.

Some people also slowly push down the throttle pedal fully once the red lightning bolt goes away and slowly release the pedal once the check engine light stops flashing.

Go for a test drive, have fun.



If you still have issues check to make sure the pins are in the right orientation, position, and that they are seated fully.

 

[Spsully]

I am humbled by your ability to clearly communicate an extensive electrical repair. I have multiple drawers in my tool box with electrical tools and this type of work is pretty basic for me. But you just made it so everyone with the courage to try will be able to do the same repair. Being able to do it is one thing, but being able to teach is next level. My hat is off to kind sir.

 

[porambo]

I am humbled by your ability to clearly communicate an extensive electrical repair. I have multiple drawers in my tool box with electrical tools and this type of work is pretty basic for me. But you just made it so everyone with the courage to try will be able to do the same repair. Being able to do it is one thing, but being able to teach is next level. My hat is off to kind sir.

Thank you I'd like to think that this is me giving back to the community. I'm an engineer for my day job and sometimes I have to solve and document things not all that different from this, such as adapting something off the shelf to replace unavailable parts. Hopefully this info can help keep some of these trucks out of the wrecking yards for a good long while.

 

[Tominator223]

Yes, good job explaining that repair. I’ve had the random red bolt since 04 when I got my truck new. 400k on truck now. (Q cab 5.7.) Still get the bolt once in awhile.( Now I’ll know where to look. Thank you.) One gas station I’ve gone to always gives me the red bolt. I turn left twice then right then left , when leaving the fuel pump.(Short turns)& bam red bolt. Also engine looses all power & if you don’t notice the red bolt is on it can be unnerving . Especially if pulling into traffic. Thanks again for this info

 

[SavedByGrace]

DUUUUUUDE!!!!!!!

I have been trying to diagnose this exact issue now for going on 2 years! I have posted in about 15 different places and not ever received anything close to a possible solution.

I was even told the TPS breaks were SUPPOSED to do that (!!!!). I ALMOST wen the merc route but gave up after someone told me the breaks were the software or sth ridiculous. https://www.scannerdanner.com/forum...iving-me-nuts-been-struggling-for-months.html

Now im not getting any codes or lights - but my tps is continuously dropping. I did to the test according to the Timbo APPS website confirming for dual voltage also, concluding my sensor is in fact ok- I might actually wire it direct to the ecu as well.

I am batlting 8mpg town driving the truck empty (2003 ram) having replaced a bazillion parts already.

My tps graph stationery: firstly at 16%, secondly it does this with no input on pedal - part throttle same thing, keeps dropping out like that- wondering if this could cause bad mileage?

 

[porambo]

DUUUUUUDE!!!!!!!

I have been trying to diagnose this exact issue now for going on 2 years! I have posted in about 15 different places and not ever received anything close to a possible solution.

I was even told the TPS breaks were SUPPOSED to do that (!!!!). I ALMOST wen the merc route but gave up after someone told me the breaks were the software or sth ridiculous. https://www.scannerdanner.com/forum...iving-me-nuts-been-struggling-for-months.html

Now im not getting any codes or lights - but my tps is continuously dropping. I did to the test according to the Timbo APPS website confirming for dual voltage also, concluding my sensor is in fact ok- I might actually wire it direct to the ecu as well.

I am batlting 8mpg town driving the truck empty (2003 ram) having replaced a bazillion parts already.

My tps graph stationery: firstly at 16%, secondly it does this with no input on pedal - part throttle same thing, keeps dropping out like that- wondering if this could cause bad mileage?

View attachment 518551

16% sounds like a little high for idle. So definitely looks like something going on there. Probably multiple things, probably wiring, at the same time. Honestly with a throttle input like that to the truck I'm surprised it would run at all. There would be some times where my TPS% looked not that different from your graph. 8mpg also sounds not great for city driving I would check the compression on the engine and double check any exhaust restrictions. Even with this happening I could get 18+ mpg (according to trip meter) at 60mph. After replacing the APPS and wire to the throttle body my TPS% is rock solid reliable, never dipping to 0% watching it the whole time for more than a half hour done several times.

 

[porambo]

Yes, good job explaining that repair. I’ve had the random red bolt since 04 when I got my truck new. 400k on truck now. (Q cab 5.7.) Still get the bolt once in awhile.( Now I’ll know where to look. Thank you.) One gas station I’ve gone to always gives me the red bolt. I turn left twice then right then left , when leaving the fuel pump.(Short turns)& bam red bolt. Also engine looses all power & if you don’t notice the red bolt is on it can be unnerving . Especially if pulling into traffic. Thanks again for this info

That is unfortunate. That's somewhat good that you know at least when the red lightning bolt comes back. After I changed the APPS sensor I was still getting the red lightning bolt maybe on 25-40% of my trips. It was almost always a few miles from my house when the engine was not all the way warmed up, but it was pretty consistent. Maybe 5% of the time I would get it not during the warm up cycle. I changed my EGR this afternoon with a Dorman unit and the truck drives much better. I had replaced it with a standard one maybe 5 months ago, but it didn't fix the issue. The only other odd symptom that I had was that the idle would climb up abnormally after I put the truck in park, but not all the time. That is gone now. Will continue to monitor, but I think this was the trick at least in my case.