P046C and P2610 on LMM

[rgullett83]

I am having some troubles with those two codes, I installed a garrett avnt 3794 on this truck, before any tuning changes were made, the truck threw these 2 codes The truck has had a blocker plate installed since new. I set the codes to non emissions no mil, tried setting them to not reported no mil, they would still kick the MIL on. I took the truck into the dealership today, reprogrammed it to stock form with the Tech II, came home and started from scratch, and still have the 2 codes present. I found a TSB for the P2610 code on an LBZ, that stated to leave ign. off for 90 secs, and then unplug the ECM connectors and leave unplugged for 90 secs, then plug back in and clear codes, guess what still have the 2610 code any suggestions?

 

[Fingers]

P046C is an Feedback error with the EGR. That is, the EGR position sensor is not returning reasonable values from ECM commands to the valve.

The P2610 is normally an internal ECM problem. However, if you have a stray voltage source coming into the ECM, that will tickle it too. This would come from a short, even a mild short, somewhere in your harness.

Several people have found the harness worn through where it loops down across the fender well on the driver's side. I would look there first.

 

[LBZ]

P046C is an Feedback error with the EGR. That is, the EGR position sensor is not returning reasonable values from ECM commands to the valve.

Hmmnn. I have my egr blocked and all the egr stuff shut-off and I occasionally got this code as well. What happens if a guy leaves it unplugged with all the MIL's turned off?

 

[rgullett83]

will do fingers, I am gonna try and get this thing for the weekend, to do some investigating, if I get the other truck in my garage done.

 

[slowlmm]

when is the last time you updated you efi ? theres a few redundant dtc in new versions for those codes

 

[rgullett83]

Last week or so, Cindy told me there is a new update, that I am installing now.

 

[rgullett83]

Picked the truck up this morning, no light on codes were still hiding in the back ground.

 

[MMLMM]

I ALWAYS have that code 046c in the background. I have played with efi many many times on the issue. Just leave it in the background. Remote start and everything will still work. There is no real solution for it right now. Even changing egr parameters wont help....

 

[Fingers]

There is nothing in EFI that I know of for the P046Cs. The dealer has a reflash that has helped many trucks, but they are tweeking a table not seen in EFI. Basically, how far off the commanded position the EGR sensor can be from the command position.

 

[rgullett83]

I can read data with the key off, with the tech II, so that tells me that there is voltage coming into the ecm, keeping it awake. for a min or so only, and then it goes to sleep. like it should.

 

[rgullett83]

I removed the UBEC with the key off, and started probin with test light, found circuit 3740 has power to it, but it slowly fades with the test light.

 

[rgullett83]

circuit 3740, is battery voltage supplied to the audio amplifier, so now I am really sscratchin my head Am chasin my tail, or on to something? I think, I will go look over the harness again as you stated to do Jon.

 

[EFI Support]

rgullett83, if you want to Email your tune to support@efilive with a reference note on what it is all about we will have a look and see what can be done to kill this EGR DTC. It will involve some trial and error but it's really the only way we can try to get to the bottom of it for you.

Cheers,
Cindy

 

[rgullett83]

At the moment, I am not to worried about the EGR code, the glow plug controller code, is what is causing the light to illuminate now. I think it is tied into the 2610 code that is setting also. I went to the dealership tonight after work, and tinkered with it, and you can still read data with the scan tool after the key is shut off, however if I remove the powertrain relay, the ecm powers down. reinstall relay no data until key is turned on as it should be. The ECM sends a ground signal to the powertrain relay coil, to turn on multiple ign 1 inputs. So my thinking right now, is that the ecm is faulty, but also the ecm receives a serial data wake up signal from the BCM. Got tired of looking at it, I think the either the ecm is faulty, or the bcm is keeping it awake. any more suggestions?

 

[rgullett83]

I will wait to see if I get these other issues resolved Cindy, and go from there, at the current state I dont believe it is an issue with the tune, or any of the EFIlive software. Thanks again to all those who are giving assistance.

 

[rgullett83]

Did I scare everyone off?

 

[rgullett83]

update, last week a new ecm was installed under warranty at the dealer, no fix for the P2610, or the p064c. I stayed there friday evening and we went through everything again, and after speaking with the owner again, we found out that he had been playin around in the underhood fuse block, upon further checking, we found that several of the fuses were not making good connection, due to either test light probing, or installation of a fuse tap, replaced the underhood fuse block and all is well. I was always told by my instructor in college never overlook the obvious and we had done exactly that, but alas it is fixed now

 

[MMLMM]

update, last week a new ecm was installed under warranty at the dealer, no fix for the P2610, or the p064c. I stayed there friday evening and we went through everything again, and after speaking with the owner again, we found out that he had been playin around in the underhood fuse block, upon further checking, we found that several of the fuses were not making good connection, due to either test light probing, or installation of a fuse tap, replaced the underhood fuse block and all is well. I was always told by my instructor in college never overlook the obvious and we had done exactly that, but alas it is fixed now

im confused, did code p064c go completely away now?

 

[rgullett83]

Yes the p064c is completely gone, however the p046c (egr code) still sets in the background, but is not tripping the MIL so all is well

 

[MMLMM]

Yes the p064c is completely gone, however the p046c (egr code) still sets in the background, but is not tripping the MIL so all is well

oh oops I had them mixed up. Yes I and I think everyone else has that code stay on, but just in the background. Even when set to not reported.

EFI support: is there a reason why when a code is set to not report it goes away but not in the background?