2018 Kenworth T680 Intermittent U0753 and Instrument Cluster Blackout

Question

My dash keeps cutting out and showing a 'Data Link Failure' message while I am on the highway. This is throwing a U0753 fault code along with some lighting module errors, and sometimes the gauges just drop to zero before coming back a minute later. I suspect a harness rub somewhere behind the dash or at the firewall connector.

Mike Reynolds · Accepted Answer

Found the issue at the firewall pass-through connector. There was a pin fret corrosion on the J1939 High wire (Yellow) at connector P001. I cleaned the pins with DeoxIT, re-tensioned the female side of the terminal, and applied a bit of dielectric grease. Total cost was just the shop supplies and 4 hours of teardown and tracing, but the U0753 hasn't returned in 5,000 miles.

Lina Brooks · Answer

I have seen this happen on the T680 where the harness rubs against the steering column support bracket. Pull the kick panel under the steering wheel and look for any exposed green/yellow twisted pair wires.

fleet_chief_42 · Answer

Check the CECU (Central Electronic Control Unit) connectors. Sometimes moisture gets into the cab bulkhead and causes pin corrosion which drops the V-CAN communication briefly.

turbo_tony · Answer

Check the J1939 backbone resistance at the diagnostic port. You should see 60 ohms with the batteries disconnected; if you see 120, you have a broken leg in the bus, and if you see 0, you have a short.

2018 Kenworth T680 Intermittent U0753 and Instrument Cluster Blackout

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