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Can someone help me figure out how to get Oil Pressure onto the CAN bus from the ECU?

I have mapped RPM and Coolant temp using the PE message standard, but apparently that standard doesn't contain Oil Pressure, so I've been trying to find it in the Bosch or J1939 standards with no luck.

Does anyone know how to map it, i.e., the message id, offset, length, multiplier, adder, and LSB/MSB?

Thanks in advance for any pointers!

If you have a newer AIM or CDS system you should already have a map in the software, others I am not sure.

Assuming you have the PE3 CAN Bus setup configured to send the Bosch MS4.3 protocol, set the transmit rate to 1000 kbit/sec (1 Mbit/sec). Be sure the Bosch MS4.3 message ID 0x771 is selected (we normally select all the messages).

The oil pressure appears on a compound message sent to standard address 0x771, the first byte must be 03 (compound identifier), then the oil pressure will be found at offset 7, length 1, units are bar with 0.0512 bar/bit, to convert to PSI I believe you would use a multiplier of 752 and a divisor of 1000 (or a multiplier of 752.64 if you can do floating point), addr = 0.

Oil Pressure should be updated every 100 ms.

drop me an email, and I will send you what I think you need to decode the entire MS4.3 protocol that the PE3 sends.

David Ferguson
ferg@veracitydata.com