Cat D400E data link/ ECM problems.

[cb75]

Working on a Cat D400E articulated dump truck. Having wiring / electrical issues with the data link, code 030 248.02 is active. ET will not communicate with the truck now. I did get my laptop to connect once and It's telling me that the power train ECM is "unavailable". Was still getting data from it tho. Going to do all the checks outlined in that codes troubleshooting guide. And now ET won't connect again. How would one determine if an ECM has failed? Only ECM I've ever had to replace was on a non Caterpillar machine.

The monitor will also show warning lamps on for the bed not in float, and the steering oil pressure indicator. Going back to it now to Troubleshoot code 248.02 and why those indicator lamps are on.

It's a D400E S/N 8PS00686 with a bit over 13,000 hours.

Also just replaced the lock up clutch solenoid as it had failed and was showing another active code. It is ok now.

 

[Mark250]

hi a couple of questions
is the truck running?
what coms adapter 2 or 3 are you using?
if 2 have you tried different port and port settings?
if 3 connect to diagnostic connector only. is the red light on?
plug in to the laptop only is the red light on?
if no light on, on either connection you have faulty coms cables
have you tried to communicate through ATA (change comm settings in ET)
if all that is ok
make up a jumper connection and hook directly in the ECM

if you need pin outs let me know

 

[cb75]

I'm using com adapter 3. It will communicate with any other machine I try it on. After applying power, only the red light is on.
The truck is running, it starts, will release the park brake and will go in gear and move. When the " not in float " indicator comes on the truck won't shift which is normal for when hoist lever is not in float.
Since it will start and move I guess that the PT ECM is ok.

After going thru the troubleshooting guide for code 030 0248.02 (which is still active) I've found that there is a short in the harness in the data link wires. I will get my notes and report back with exactly which wires are shorted.

 

[mrappels]

would love to hear your feedback on this.
never seen the d400e, seems unlikely that its an ecm problem, but not impossible. had a look on the schematic, maybe look for rubbing points along the harness, or corrosion on connection 17..? how long has that light been there for? one way to check if its the ecm would be to swap one out with another machine if at all possible..

good luck man.

 

[mrappels]

hi a couple of questions
is the truck running?
what coms adapter 2 or 3 are you using?
if 2 have you tried different port and port settings?
if 3 connect to diagnostic connector only. is the red light on?
plug in to the laptop only is the red light on?
if no light on, on either connection you have faulty coms cables
have you tried to communicate through ATA (change comm settings in ET)
if all that is ok
make up a jumper connection and hook directly in the ECM
View attachment 172701
if you need pin outs let me know

hi mark, please could you show me how to connect the et directly to the ecm?? that would be really handy.

 

[Mark250]

Hi mrappels , no problem ,I will put something together later today
Mark

 

[cb75]

Don't have another D400E to swap ECM's with. The warning lights started coming on out of the blue. Truck was hauling dirt all week with no problems and then this started.
I now think the ECM is fine and there is a wiring problem. Spoke with a Cat mechanic who had a very similar problem on a different D400E which turned out to be a bad diode.
I haven't been working on this problem the last few days. I'll check with the guy who is and get up to speed on his
progress and may have to get back on it on Saturday.

Years ago this same truck had an issue to where the gear shifter control would lose neutral calibration every night. Every morning we'd have to recalibrate it. It was a real simple task, just put it in neutral and hold in one of the two buttons on the shifter for 30 seconds and you had it recalibrated for the day. That went on for about a month and one day it just stopped acting up and has been fine ever since.

 

[Mark250]

Hi cb75,the hoist float indicator is controlled be the ECM via the cat data link
have you checked the hoist lever PWM out percentage on the monitor, if the hoist sensor is faulty it may be giving incorrect info the ECM and locking the transmission in the default first gear position.
have you tried changing the body float gear limit in ET
Mark

 

[Mark250]

hi moderators if you think this Reply should be moved please do so
Mark

hi mark, please could you show me how to connect the et directly to the ecm?? that would be really handy.

Hi mrappels,it is quite easy to power up an ECM via a different power source than the machine. there are a couple of things to be aware of
1- the ECMs will run on either 12v or 24 volt
2- even though multiple power supply's and returns are indicated on electrical schematics only one B+ and one B- is required to operate the ECM for test purposes
3- generally 5 wires are needed for the ECM to communicate with ET
B+, B-,key switch B+,CDL + and CDL -
4- be aware that on highway trucks use different diagnostic plugs than machine diagnostic plugs
5- Cat uses a number different ECM's and some even look the same but the connection pin outs are different
Here is a list of common ECM's
ADAM 2 - has two forty pin connectors used ,as engine ECM
MAC- has one or two forty pin connectors ,looks the same as ADEM 2 ECM, used as machine system ECM
ADEM 3- has two 70 pin connectors used as engine ECM
ABL- Has one or two seventy pin connectors, looks the same as ADEM 3 ECM, used as machine system ECM
ADEM 4- has one seventy pin connector and one,one hundred and twenty pin connector, used for engine and machine systems
ADEM A4-E2 Has two 64 pin connectors used as engine ECM on later common rail engines (Perkins/Mitsubishi)
for the ADEM 2 ECM pin outs
B+ to pin#4 also connect to diagnostic connector pin#A
B- to pin#5 also connect to diagnostic connector pin#B
CDL+ to pin#9 also connect to diagnostic connector pin#D (green)
CDL- to pin#3 also connect to diagnostic connector pin#E (brown)
switched input B+ to pin#6
For MAC ECM
B+ to pin#1 also connect to diagnostic connector pin#A
B- to pin#2 also connect to diagnostic connector pin#B
CDL+ to pin#9 also connect to diagnostic connector pin#D
CDL- to pin#3 also connect to diagnostic connector pin#E
switched input B+ to pin#40
For ADEM 3 and 4 ECM (engine)
B+ to either 48,52 or 53 also connect to diagnostic connector pin#A
B- to either 63,65 or 67 also connect to diagnostic connector pin#B
CD+L to pin#8 also connect to diagnostic connector pin#D
CD-L to pin#9 also connect to diagnostic connector pin#E
switched input B+ to pin #70
For ADEM 3 and 4 (machine)
B+ to pin#1 also connect to diagnostic connector pin#A
B- to pin #2 also connect to diagnostic connector pin#B
CDL+ to pin #8 also connect to diagnostic connector pin#D
CDL- to pin#7 also connect to diagnostic connector pin#E switched input B+ to pin #58
for A4 E2 ECM
B+ to pin#1,2,9 or 10 also connect to diagnostic connector pin#A
B- to pin #7,8,15 or 16 also connect to diagnostic connector pin#B
CDL+ to pin #23 also connect to diagnostic connector pin#D
CDL- to pi #24 also connect to diagnostic connector pin#E
switched input to pin#40

some cat part numbers that may be useful
diagnostic connector P# 8T8736
A3 ECM connector 160-7689
sockets for above 9x3402
A2 ECM connector 3E6286
A3 ABL ECM connector 160-7690
MAC ECM connector 101-0205
A4E2 ECM connector 245-1042
sockets for above 267-9572
here is some screen shots of ECM ET stand alone Data

 

[Mark250]

the on highway truck ECM's and some machines i.e. D400E communicate to ET via the ATA protocol. in this case the CAT data link is not used
the ECM pinouts will be in the same position but the connections to the diagnostic plug will be different (not using the on highway adapter)
For ADEM 3 and 4 ( Engine ECM )
B+ to pin# 48,52 or 53 also connect to diagnostic connector pin#A
B- to pin# 63,65 or 67 also connect to diagnostic connector pin#B
ATA+ to pin #8 also connect to diagnostic connector pin#J
ATA- to pin #9 also connect to diagnostic connector pin#H
key switch B+ to pin#70
Mark

 

[rmllarue91]

Hey guys I have a d400e 2yr00259 that had lots of electrical issues most went back to ground and harness issues. I would clean and fix all grounds and inspect harness then back probe some electrical components and watch ground resistance I think goal is 10 omhs or less. Good luck

 

[cb75]

Mark250, I will finally get back on this job (D400E) this afternoon. I will check the hoist lever switch.
Also thanks for the ECM power info. I will definitely print this out and keep it in the drawer of my box with all my other important info and paperwork. As it will come in very handy from time to time. Thanks again!

 

[cb75]

Well, the problem has been solved. Another mechanic found a short in the harness somewhere on the engine. He repaired it and all is back to normal. I didn't get to see exactly where the short was or which wire.

A big thank you to Mark250 for the valuable info on the ECM's. Very much appreciated.

 

[mrappels]

Well, the problem has been solved. Another mechanic found a short in the harness somewhere on the engine. He repaired it and all is back to normal. I didn't get to see exactly where the short was or which wire.

A big thank you to Mark250 for the valuable info on the ECM's. Very much appreciated.

Its a bit deflating when you sink your teeth into a problem, only to have someone fix it on the other shift. But that's what team work is about.
Glad the issue was sorted though.