New member, Singleviu gauges in R2.8 conversion

[DaveG]

Just a brief intro to start with. I and my family live in S.E. Oregon USA. I and my 2 sons swapped in a new Cummins R2.8. The new engine, clutch, and 5 speed manual tranny have 85 engine hours on them. We put in a new built rear axle with locker a couple years earlier. The front axle and transfer case are original.

It's being driven both on and off-road, but it's still a work in process. I recently received most of 6 VDO Singleviu gauges. I'm planning on running all but the speedometer and fuel level from Cummins j1939 over CANbus data. The GPS speed sensor and fuel gauge have not arrived yet. All other data must be available on the network as the Murphy gauge displays them. Questions and problems remain.

I want to thank the forum admins for granting me access and beg members for forgiveness as my vehicle is a '98 Jeep Wrangler TJ. The Jeep forums are not much help as Jeepers aren't doing many R2.8 swaps themselves and Singleviu gauges seem to be unheard of. I hope our knowledge can help others and we can learn from you.

 

[DaveG]

Has anyone run a Singleviu tach on the same bus with the R2.8 and Murphy gauge? Our tach displays the same engine hours as the Murphy gauge but the tach needle remains at zero while the Murphy corretly displays RPM.

With a twisted pair to can+ and can- on the ODBC2 connector, resistence is 60 ohms with no Singleview gauge connected or another unconfigured Singleview connected. This and the hours displayed on both the Murphy and tach suggests we have a good can bus correctly terminated. It also suggests the tach is correctly configured to can rather than analogue. The engine runs fine which also indicates a good can bus.

Concerning is that with the tach hooked up, resistence drops to 40 ohms. Any ideas?

 

[brdhmltn]

I have not used Singleviu

There is a second CAN connection in the harness. Have you tired that? And there is a termination resistor in the harness that you may have to play with. I have been writing a program on a canbus ESP32 hat to convert J1939 to OBD2 so I can use banks iDash gauges... it's just a side thing i have no timeframe for completing that I thought would be fun to learn. I have the rpm kind of working, i think it's byteswapping the data.

I have the murphy gauge on its harness connection, then use the "OBD" plug - which is J1939 can on an OBD plug - to run to my ESP32 hat and then output the ESP32 hat to the iDash. Works fine and do not interfere. I have my can hat term resistors set to 120 ohms on both channels (in data from engine, out data to iDash)

What i have found going through the programming registers for J1939 is that there are really a lot of custom registers per manufacturer and it's difficult to cross reference. I built the output of my terminal on the ESP32 to output all received J1939 messages and that gave me a list to google and find the right reference to convert the data into an OBD2 message for the iDash.

Does the Singleviu give a list of the J1939 registers it supports?

Edit: Here is a sheet link I started from to translate J1939 to OBD2

CAN ID to J1939/N2K PGN converter

docs.google.com

 

[brdhmltn]

I think this manual should help you out if you don't have it. It shows the wiring, where the termination resistor should be (120 ohms) and which variants and PGN's are being used. Pages 20-23. Second link is image to how termination resistors should be set up. Only before the first and after the last nodes.

https://www.vdo.com/media/746713/en_user-manual-singleviu_22-201801.pdf

https://canlogger1000.csselectronics.com/img/terminal-resistor-buy-low-cost-adapter-db9.svg

I think with this you shouldn't have to mess with the term resistor in the harness or the second input at all.

 

[DaveG]

Thank you for the links. I took a look at CSSelectronics.com. The Guides page looks like where I need to start.

The can variants and PGN's you mention are my main concern. I'll try to determine if they are identical across Cummins engines, year of manufacture and etc. Why the Murphy gauge can display tach data while the VDO tach does not is my current focus.

 

[DaveG]

We figured out the extra termination resister issue. Snip the red wire jumper in the 12 pin connector pins 3 and 4 to remove it. Resistance is now 60 ohms

My son called Cummins and learned that Cummins follows the j1939 standard PGN/SPN. It's not proprietary. He called VDO and received the same answer.

Next problem: I misconfigured the low RPM limit to 1400 instead of 400 in initial tach configuration. Mine idles at about 800 so tell-tale 1, a red exclamation point in red triangle, is displayed. I bet the out of range is why the needle doesn't move. I fixed the configuration, but I haven't figured out how to clear it. Restarting didn't clear it. Ariel, can you help?

 

[brdhmltn]

The manual shows the scale for RPM is x 100. Do you have to take that into account in the setting? I.e. for 800 rpm does the setting need to be 8? It shows the range as 0 to 40.