CAT 259D - No Crank E459-2 Code

[acolar]

Hi Guys
Trying to help my son diagnose a 2015 CAT 259D with 2092 hrs, serial FTL03587.
Initial symptom was no crank due to low battery, jump started and ran all day.
Drove it onto trailer and off trailer into the shop and next start attempt was a no crank with the E459-2 code.
Charged battery , checked a number of grounds, checked fuses and still no crank with E459-2.
Looked over the couple of posts on the site and will check the engine grounds and diode harness at rear.
Found a power block inside engine compartment left side forward of fuel filter with a B+ lead from battery and
a couple of 50A fuses that looks very corroded but i was able to read battery voltage on the posts of the power block.
Was going to try and clean up the interface but worried if I try to break the nuts free the studs may break due to corrosion.
No schematic and unfamiliarity with CAT component locations is really hampering the troubleshooting.
Wondering if a Engine ECM or Machine ECM power relay is not engaging preventing CAN bus traffic between ECM's?

Anyone know how I can find an electrical schematic for this machine please? Thanks in advance.

Tony

 

[acolar]

Hi Guys
Trying to help my son diagnose a 2015 CAT 259D with 2092 hrs, serial FTL03587.
Initial symptom was no crank due to low battery, jump started and ran all day.
Drove it onto trailer and off trailer into the shop and next start attempt was a no crank with the E459-2 code.
Charged battery , checked a number of grounds, checked fuses and still no crank with E459-2.
Looked over the couple of posts on the site and will check the engine grounds and diode harness at rear.
Found a power block inside engine compartment left side forward of fuel filter with a B+ lead from battery and
a couple of 50A fuses that looks very corroded but i was able to read battery voltage on the posts of the power block.
Was going to try and clean up the interface but worried if I try to break the nuts free the studs may break due to corrosion.
No schematic and unfamiliarity with CAT component locations is really hampering the troubleshooting.
Wondering if a Engine ECM or Machine ECM power relay is not engaging preventing CAN bus traffic between ECM's?

Anyone know how I can find an electrical schematic for this machine please? Thanks in advance.

Tony

Went back to the machine after dinner for more diagnosis. It will crank if the lap bars are down - so its really a Crank - No Start. Same error message displayed E459-2.

Found a fuse box under the cab and measured voltages present with the key off. Not sure what the rectangular devices are with the two pin connectors - maybe solid state relays?

Thanks

 

[Nige]

This is one I haven't come across before - Engine Power Mismatch. Not sure how that one occurs without something being amiss in the EPROM side of the ECM. That P/N of ECM is used on a number of different models and needs corresponding software installed in it to provide the "machine identity".
I'll send you an electrical schematic.

 

[Chrisso]

First for me also. Found this...

"At start-up, the machine ECM requests the engine ECM for the engine power rating by CAN communication. If the machine ECM does not receive a response, the E459-2 code will become active. In this situation, Cat ET will also not be able to connect to the engine ECM. This scenario is the most common occurrence of the E459-2"

Wondering if a Engine ECM or Machine ECM power relay is not engaging preventing CAN bus traffic between ECM's?

I'd say you're probably on the money. Bad earth strap, bad power or gnd to engine ECM, need to check all harness grounds on the engine block, CAN wiring, etc

 

[Nige]

G'day Chrisso. Can I ask where or how you found that explanantion.? (Still on a learning process with SIS2.0.)

 

[Chrisso]

Just PM'd ya Nige, but basically...



It's in a TIB so depends on access level I guess

 

[acolar]

Thanks Nige & Chrisso. Back to the machine with voltmeter and schematics.

 

[acolar]

Good Day
Just wanted to clarify the symptom which was actually a Crank - No Start with a Faulted indication in the Advanced Display and error E459-2.



Checked for power to engine ECM and found no voltage on the ECM Power Relay Output contact #87. 20A fuse was good
checked for power at ECM Pwr Rly coil pin 1 and Machine ECM was providing 12v to pin 1.
Determined that ECM Pwr Rly Coil pin 2 was not being grounded by Engine ECM.
Traced pin 2 circuit (C903-C59-BU18) up to Conn 4 (Round 31 pin) at rear of cab. Continuity was good to the input side of connector.
found open circuit from output side of Conn4 to engine bay Conn 28 (12 pin )
Unable to determine where exactly the open was as this is poor access to that area of the engine bay - was unable to remove ECM cover due to hoses in the way.
Built a test jumper harness to ground pin 2 of the ECM Pwr Relay coil for test purposes.
When coil pin 2 was grounded a click was heard which was relay engaging and voltage was present at relay output to Engine ECM.
Turned key on, advanced display initialized, entered access code, no fault displayed, turned key to crank engine - engine cranked and started. No errors displayed.
Root Cause of concern was an open in ECM Relay Coil ground circuit (C903-C37-BU18) somewhere between Conn4 and ECM Conn J1. This prevented communication between the Engine ECM and Machine ECM setting the E459-2 fault.


Special thanks to Nige and Chrisso for their input in helping identify the root cause.