P046c Help.

[MMLMM]

LMM with EGR blocked, EGR turned off, MIL off, not reported.

I have no light but it still comes up in the background.

Not a huge deal right now but my factory remote start won't work with it setting in background.

Any idea or help to get it to go away since its not reported? Once in a while I get a 2033 (i think) code pop up in background too and its set not to report.

Thanks.

[GMPX]

It's quite odd the remote start won't work with an EGR DTC set considering remote start was intended for cold weather starts and the EGR isn't supposed to start working until the engine is near running temperature.
Did you try raising B1503 to a higher temp (just below the value in B1504).

Cheers,
Ross

[MMLMM]

It's quite odd the remote start won't work with an EGR DTC set considering remote start was intended for cold weather starts and the EGR isn't supposed to start working until the engine is near running temperature.
Did you try raising B1503 to a higher temp (just below the value in B1504).

Cheers,
Ross

Ive done all the adjustments to stop the EGR from working (slowlmm for example gave the the parameters th change) still get the 046c code. All the other egr code stay away. My main question i guess is why its set to not report, but it still comes up in background?

I think the remote start could be something else. I thought when I had a code the remote start wont work.

Thanks.

[GMPX]

So the example parameters you have used from someone else work fine on other trucks?

Also, check if there is multiple instances of the DTC in the DTC list, don't know why but sometimes in the DTC array in the ECM there is multiple instances of certain codes, all must be switched off.

Cheers,
Ross

[fire0021]

yea works fine on mine ross but i guess for some reason there showing up on mikes i do think the remote start is another issue ? mike u can completley shut the egr off with the new tables have you tried those?

[RPM Motorsports]

Im also getting a p046c after an MPI twin install. along with p0401 and p0101

[LBZ]

Ive done all the adjustments to stop the EGR from working (slowlmm for example gave the the parameters th change) still get the 046c code. All the other egr code stay away. My main question i guess is why its set to not report, but it still comes up in background?

Thanks.

On my LBZ once in awhile I get this code as well with probably the same parameters changed to turn it off and not report.

Very strange.

[06Dmaxpwr]

Same instances on my LBZ also...codes set not to report...and still there.

[MMLMM]

BUMP

So....Any reason the code is still there although its set to not report?

Thanks.

[GMPX]

The Bosch ECM still seems to process DTC's regardless of the DTC setting in the list, this might also indicate that we have missed yet another layer of DTC controls (I can't rule that out), but for the most part it stops majority of codes.
It seems the best way to tackle the DTC's on the Bosch is to ensure it never gets a chance to run the tests in the first place.
For example you could try these settings -

{B1502} EGR Minimum Position Shutoff 100 %
{B1503} EGR Minimum Engine Temperature 140°C (284°F)
{B1504} EGR Maximum Engine Temperature -40°C (-40°F)
{B1529} EGR Cooling Monitor Upper RPM 6000 RPM
{B1530} EGR Cooling Monitor Lower RPM 5990 RPM

What this means is the ECM will never attempt to use the EGR because all those parameters are set outside normal useage limits, if the ECM is not attempting to control the EGR then it won't bother running the performance based diagnostics (which P046C is).

For P0101, you could probably get away with maxing out {C0903} P0101 Upper Limit Threshold, OR, set {C0908} P0101 Test Enable, RPM High to something that is only 100RPM above {C0907} P0101 Test Enable, RPM Low.
That would be mean the ECM will only check the MAF flow sanity between say 500 RPM and 600 RPM, in other words, it will never be a problem.

Cheers,
Ross

[MMLMM]

The Bosch ECM still seems to process DTC's regardless of the DTC setting in the list, this might also indicate that we have missed yet another layer of DTC controls (I can't rule that out), but for the most part it stops majority of codes.
It seems the best way to tackle the DTC's on the Bosch is to ensure it never gets a chance to run the tests in the first place.
For example you could try these settings -

{B1502} EGR Minimum Position Shutoff 100 %
{B1503} EGR Minimum Engine Temperature 140°C (284°F)
{B1504} EGR Maximum Engine Temperature -40°C (-40°F)
{B1529} EGR Cooling Monitor Upper RPM 6000 RPM
{B1530} EGR Cooling Monitor Lower RPM 5990 RPM

What this means is the ECM will never attempt to use the EGR because all those parameters are set outside normal useage limits, if the ECM is not attempting to control the EGR then it won't bother running the performance based diagnostics (which P046C is).

For P0101, you could probably get away with maxing out {C0903} P0101 Upper Limit Threshold, OR, set {C0908} P0101 Test Enable, RPM High to something that is only 100RPM above {C0907} P0101 Test Enable, RPM Low.
That would be mean the ECM will only check the MAF flow sanity between say 500 RPM and 600 RPM, in other words, it will never be a problem.

Cheers,
Ross

Thanks for the info Ross, Ill give that a shot too and see if that helps.

[Nor-Cal Nick]

Hey Mike, this work for your problem. Kinda having the same issue's.

[MMLMM]

Hey Mike, this work for your problem. Kinda having the same issue's.


Nope, I'm still stuck with the EGR code.

Its always in the background tho so it dont bother me.

My remote start issue was due to something else.

[Nor-Cal Nick]

What o.s. are you running?

[MMLMM]

what o.s. Are you running?

*****083