CUMMINS ECM REPAIR TIPS

**jctech** · 1st April, 2011, 03:01 AM

Originally Posted by Poptest

Hi Jctech......

Here are two serial numbers, 37187076 CPL2276 and 37218459 CPL2949.

The CPL2949 engines have the Eneserve ECMs installed on them. I replaced the Eneserves with 4067777 ECM on two engines, and programmed them with Inpower conforming to CPL2949. Engines run well but have insufficient power....can hit 600kw only at 60hz. Inpower doesn't show an alternate 2949 calibration which will uprate the engine to 800kw.

So I am now thinking of uprating them to CPL2276. Do you think this is possible? Problem is.....many parts are not identical, including the injection pumps.

Thanks much for your advice.

ESN 37187076 was built in 1999, with the now obsolete FCG (CM552) ECM (part number 3094141). It is a G2 engine.
The fuel pumps on these engines were Bosch RP39

ESN 37218459 was built in 2005, (760 HP @1800) with the GCS ECM 4067777. (1340 HP is 1000kW) It is a G1 engine.
The fuel pumps fitted to this engine are Bosch P7100, and are only be used with G1 and G2 engine ratings, higher ratings use P8500 fuel pumps with light load advance for white smoke control.

Try the G2 rating with CPL 2968, it is an EPA/CARB certified rating, and has the same number of flywheel ring gear teeth.
It is 1200 HP @1800

**Poptest** · 1st April, 2011, 12:10 PM

Thank you for suggesting CPL 2968. I will try this out as soon as the 4067777 ECMs arrive.

I've also been thinking of Calterm but have zero experience on this software. Have you tried modifying calibrations with Calterm?

**jctech** · 2nd April, 2011, 07:21 PM

Originally Posted by Poptest

Thank you for suggesting CPL 2968. I will try this out as soon as the 4067777 ECMs arrive.

I've also been thinking of Calterm but have zero experience on this software. Have you tried modifying calibrations with Calterm?

Calterm will not work with InPower calibrations

**donniemnemonic** · 2nd May, 2011, 06:39 PM

hi all
Was wondering has anyone come across a similar fault in celect ecm where fault code 255 is active but when substituted for another the code does not come up.after swapping units it has led me to believe that the fault is in the ecm internals. Any ideas as to which components may have failed here?

**donniemnemonic** · 5th May, 2011, 05:34 PM

Originally Posted by donniemnemonic

hi all
Was wondering has anyone come across a similar fault in celect ecm where fault code 255 is active but when substituted for another the code does not come up.after swapping units it has led me to believe that the fault is in the ecm internals. Any ideas as to which components may have failed here?

After witch-hunting for the past 2 days I am glad to say that I managed to locate the faulty component which was a bipolar transistor. After replacing it and refitting ecm to truck the 255 code went inactive almost instantly.

**Poptest** · 6th May, 2011, 05:29 PM

Originally Posted by donniemnemonic

After witch-hunting for the past 2 days I am glad to say that I managed to locate the faulty component which was a bipolar transistor. After replacing it and refitting ecm to truck the 255 code went inactive almost instantly.

Please post picture location of bipolar transistor.

Thanks.

**donniemnemonic** · 6th May, 2011, 08:35 PM

Originally Posted by Poptest

Please post picture location of bipolar transistor.

Thanks.

Will post pics once i have made some. Tell me have you come across similar faults?

**Poptest** · 7th May, 2011, 01:16 AM

Originally Posted by donniemnemonic

Will post pics once i have made some. Tell me have you come across similar faults?

Yes I have, and 255 is common. Truck driver and/or mechanic sometimes puts a jumper wire between Bat+ and pin 16 of actuator harness.

I've never tried repairing ECMs though. I replace any faulty ECM outright. That's why I'd like to learn.

**Juanincho** · 13th May, 2011, 07:30 PM

Hi folks, anyone knows if there is some kind of cross reference guide for calibrations, I mean, with a given ECM code you can look at the cpl, hp, torque, etc, it would be useful for looking at calibrations without going into Insite. Thanks everyone !

**donniemnemonic** · 14th May, 2011, 09:22 PM

Originally Posted by Poptest

Yes I have, and 255 is common. Truck driver and/or mechanic sometimes puts a jumper wire between Bat+ and pin 16 of actuator harness.

I've never tried repairing ECMs though. I replace any faulty ECM outright. That's why I'd like to learn.

sorry m8 have manged to take a photo of ecm pcb but now I need to edit it so as to identify the transistor I mentioned. Just needed to know before I did post it if you have electronic skills cause this is not the only component failure that may trigger fault code 255 but there are more that could cause it as well.
Regards
Donniemnemonic...........

**Poptest** · 16th May, 2011, 09:45 AM

Originally Posted by donniemnemonic

sorry m8 have manged to take a photo of ecm pcb but now I need to edit it so as to identify the transistor I mentioned. Just needed to know before I did post it if you have electronic skills cause this is not the only component failure that may trigger fault code 255 but there are more that could cause it as well.
Regards
Donniemnemonic...........

Hello Donnie,

I am quite familiar with electronics, but have never attempted to repair/replace any internal ECM parts.

I also realize that the ECM you repaired may already be installed and running on the truck. If this is the case, I don't think you should go into the hassle of dismounting the ECM to take pictures.

Thank you anyway. Your post has been an eye opener to me. I will try to repair an ECM. We have lots floating around here from previous jobs.

Byebye.................. Poptest

**Poptest** · 16th May, 2011, 09:51 AM

Originally Posted by Juanincho

Hi folks, anyone knows if there is some kind of cross reference guide for calibrations, I mean, with a given ECM code you can look at the cpl, hp, torque, etc, it would be useful for looking at calibrations without going into Insite. Thanks everyone !

Hello Juanincho,

I always use Quickserve together with Insite to determine the correct ECM calibration. I beleive this is the best way.

**raphael** · 25th May, 2011, 08:55 PM

i have a cummins celect whit this problem no 5v for eeproms . i check all the transistors, diodes but i dont find the problem , any help?

**donniemnemonic** · 25th May, 2011, 10:48 PM

Originally Posted by raphael

i have a cummins celect whit this problem no 5v for eeproms . i check all the transistors, diodes but i dont find the problem , any help?

Hi m8.
Do you have a 100 plus volts on the large green capacitor just below the round black inductor housing on your driver pcb? Also check the miniature transformer on the same board should have 12v on some pins and 5v on the other pins. I am assuming that your ecm is unable to communicate with insite or similar otherwise then it would be working okay.