Looking for M1078A1 ABS troubleshooting guide

[hike]

While awaiting the arrival of the diagnostic kit: found another older HP laptop in the closet. This will become a dedicated LMTV laptop, windows 10 installed, no serial port, downloaded suggested software; started reading the ABS manual from the beginning rather than jumping to troubleshooting. All four ABS sensors click at power up in front to rear, side to side order, dash light comes on, goes off, then immediately back on.

Hopefully diagnostic kit will arrive before the weekend—

 

[aw113sgte]

Not having any luck reading from the ABS ECU. It seems to connect but seems to give me trash data. This is with a hardware serial port, DPA 3 Plus. Any ideas?
No issues with Dana, Cat ET, although the dearborn software errors out fairly quickly.

 

[hike]

New toy arrived this morning: most parts look new, last calibration done in 2019. Good thing it is Friday, if UPS brings the serial to USB cable I may need to leave early—

 

[hike]

New toy arrived this morning: most parts look new, last calibration done in 2019. Good thing it is Friday, if UPS brings the serial to USB cable I may need to leave early—

View attachment 909120

hmmm. Well we connected the DPA III plus using the USB to serial. Computer talks to the Dearborn adaptor and we updated the firmware succesfully. Our M1078A1 talks to J1708 (it blinks red), though apparently not to J1939 or J1850 (no blinking, except while updating the firmware). Neither the Dearborn software, nor the Dana software achieve a connection.

I have yet to find any help documentation for the DPA III plus, DPA 5 documentation has offered some thoughts, though not sure those are appropriate to older firmware. Wondering if this means we have a harness issue? Very reticent to spend another $400 for Wabco software with where I am standing right now.

You all have helped me get here; any next suggestions?

 

[Lostchain]

hmmm. Well we connected the DPA III plus using the USB to serial. Computer talks to the Dearborn adaptor and we updated the firmware succesfully. Our M1078A1 talks to J1708 (it blinks red), though apparently not to J1939 or J1850 (no blinking, except while updating the firmware). Neither the Dearborn software, nor the Dana software achieve a connection.

I have yet to find any help documentation for the DPA III plus, DPA 5 has offered some thoughts, though not sure those are appropriate to older firmware. Wondering if this means we have a harness issue? Very reticent to spend another $400 for Wabco software with where I am standing right now.

You all have helped me get here; any next suggestions?

With the ignition to the truck turned on and the DPA hooked to the truck, what does the Dearborn Adapter validator show? Screenshots please.

 

[aw113sgte]

hmmm. Well we connected the DPA III plus using the USB to serial. Computer talks to the Dearborn adaptor and we updated the firmware succesfully. Our M1078A1 talks to J1708 (it blinks red), though apparently not to J1939 or J1850 (no blinking, except while updating the firmware). Neither the Dearborn software, nor the Dana software achieve a connection.

I have yet to find any help documentation for the DPA III plus, DPA 5 documentation has offered some thoughts, though not sure those are appropriate to older firmware. Wondering if this means we have a harness issue? Very reticent to spend another $400 for Wabco software with where I am standing right now.

You all have helped me get here; any next suggestions?

View attachment 909145

When using my computer with the serial to USB adapter, I have to plug it into and out of the diagnostic port several times before it will establish connect. There are lots of serial to USB adapters of various quality too.
It did have a faster and more stable connection with my laptop with a physical port.

 

[hike]

With the ignition to the truck turned on and the DPA hooked to the truck, what does the Dearborn Adapter validator show? Screenshots please.

Yes. Diagnostic goes red, connection failed. I have tried every option choice presented. Give me a moment and I'll run back out and take photos—

 

[hike]

With the ignition to the truck turned on and the DPA hooked to the truck, what does the Dearborn Adapter validator show? Screenshots please.

I wish I had videoed the firmware update, though I watched intently. All the J lights winked and blinked, Mode/DPA Pass blinked, received a successful message in the update software on the laptop.

J1939 not blinking feels ominous to me, with my, admittedly, lack of experience using these tools—

 

[hike]

When using my computer with the serial to USB adapter, I have to plug it into and out of the diagnostic port several times before it will establish connect. There are lots of serial to USB adapters of various quality too.
It did have a faster and more stable connection with my laptop with a physical port.

Good comments. Power and J channel blinking appear to come from the truck side. When you plug in truck side what indicators do you see on your DPA adaptor?

 

[aw113sgte]

Good comments. Power and J channel blinking appear to come from the truck side. When you plug in truck side what indicators do you see on your DPA adaptor?

1708 and 1939, but those seem to be on even when the computer can't talk to it. I do have the exact same dpa3+, using on a 2007 model

 

[hike]

1708 and 1939, but those seem to be on even when the computer can't talk to it. I do have the exact same dpa3+, using on a 2007 model

Right. Ours not blinking on J1939 is not a good sign. <CRAP!> another issue to address. Now how to determine if it is tool or truck—

 

[GeneralDisorder]

Do you have access to an oscilloscope?

The 3126b CAT computer should be putting out J1939. Check that your diagnostic port has proper power and ground and then look at the scope trace of the data pins.

One thing I have found - especially with the 3126b trucks - the data connection is not as stable. I've had them not be able to reliably flash ECM's and had to pull the ECM and do the flash on the bench.

Definitely address all harness to chassis grounds and especially battery terminals, LBCD connections, and make sure the power distribution studs and ignition relays on the PDP are clean and tight.

Also - USB to serial adapters are notoriously poor choices for this application. I think I mentioned to you before that this whole diagnostic software business is glitchy enough on what it was designed to run on for operating system and hardware. The military uses Dell rugged laptops with hardware serial. My go-to is the Dell 5414 or 7214. The 5414 seems to do well with Windows 7 and that's what you want to stick with for this application. The 7214 is newer and Windows 7 support I'm not sure on. The screen on the 5414 is better also - larger and brighter. They are all over ebay - they have been common in police cars, etc.

 

[Lostchain]

J1939 will not blink unless you are actually communicating on the bus with that protocol. It is perfectly normal for the adapter when simply powered with no communication to only blink J1708.

The problem here is that you have picked the wrong adapter, you have selected a DPA4 Plus USB, when you do not actually have a DPA 4 Plus USB.








What you have is a DPA III Plus Serial unit and so you need to pick the correct adaptor, as per my screenshot below:

I would also make sure that your USB to Serial shows up as COM1 in windows device manager, and if it doesn't change it so it does.

 

[GeneralDisorder]

Ah - yeah that would do it. I'll have to check but I thought they both lit up on my C7 truck without the laptop connected.

Different ECM and TCM though.

 

[hike]

J1939 will not blink unless you are actually communicating on the bus with that protocol. It is perfectly normal for the adapter when simply powered with no communication to only blink J1708.

The problem here is that you have picked the wrong adapter, you have selected a DPA4 Plus USB, when you do not actually have a DPA 4 Plus USB.




View attachment 909154



What you have is a DPA III Plus Serial unit and so you need to pick the correct adaptor, as per my screenshot below:

I would also make sure that your USB to Serial shows up as COM1 in windows device manager, and if it doesn't change it so it does.

View attachment 909155

Only two choices available. No choice for 101 - DG DPA II/III/III+ - COM 1. Searched dgtech.com for older downloads without success so far.

Will check the USB to serial as COM1. Being Linux and fruit, Windows settings is a f$%&@ing nightmare—

 

[Lostchain]

Only two choices available. No choice for 101 - DG DPA II/III/III+ - COM 1. Searched dgtech.com for older downloads without success so far—

Did you follow the link I sent you on Post number #17 ?

https://www.dgtech.com/wp-content/uploads/2017/03/DPAInstall.exe

That is the link to the legacy adapter drivers.

 

[Lostchain]

Only two choices available. No choice for 101 - DG DPA II/III/III+ - COM 1. Searched dgtech.com for older downloads without success so far.

Will check the USB to serial as COM1. Being Linux and fruit, Windows settings is a f$%&@ing nightmare—

The install should look like this:



you need to pick the correct adapter:



Then you should have the correct adapter available to choose

 

[hike]

Do you have access to an oscilloscope?

The 3126b CAT computer should be putting out J1939. Check that your diagnostic port has proper power and ground and then look at the scope trace of the data pins.

One thing I have found - especially with the 3126b trucks - the data connection is not as stable. I've had them not be able to reliably flash ECM's and had to pull the ECM and do the flash on the bench.

Definitely address all harness to chassis grounds and especially battery terminals, LBCD connections, and make sure the power distribution studs and ignition relays on the PDP are clean and tight.

Also - USB to serial adapters are notoriously poor choices for this application. I think I mentioned to you before that this whole diagnostic software business is glitchy enough on what it was designed to run on for operating system and hardware. The military uses Dell rugged laptops with hardware serial. My go-to is the Dell 5414 or 7214. The 5414 seems to do well with Windows 7 and that's what you want to stick with for this application. The 7214 is newer and Windows 7 support I'm not sure on. The screen on the 5414 is better also - larger and brighter. They are all over ebay - they have been common in police cars, etc.

1— no oscilloscope;
2— will review schematic and check;
3— I have no idea how to bench flash an ECM;
4— we are working through all the electrical already replaced almost all the relays and battery disconnect, LBCD connections are next, then grounds;
5— buying another laptop is not attractive, or desirable. I appreciate this comment and bowed to purchase the current kit and reconfigure an old laptop using an OS I do not understand. Keep trying @GeneralDisorder, though tonight driving to Portland or Dallas to hire you or @fuzzytoaster sounds more appealing. I am not saying no. Let us see how I feel in the morning.

From everything shared tonight though until J1939 blinks on the DPA III plus the issue is likely truck side.

Thank you all for your thoughtful comments. You all make this a wonderful, helpful forum—

 

[hike]

Did you follow the link I sent you on Post number #17 ?

https://www.dgtech.com/wp-content/uploads/2017/03/DPAInstall.exe

That is the link to the legacy adapter drivers.

I did. And the Dana one, too. The Dana software also does not work. I think the first issue is truck side since J1939 does not blink?

 

[hike]

The install should look like this:

View attachment 909156

you need to pick the correct adapter:

View attachment 909157

Then you should have the correct adapter available to choose

I'll go there again, though I recall that link just downloading. In fact I think it downloaded several times as I didn't think anything was happening and ended up having several copies in my download folder. I do not understand windows, maybe my ineptness—