Bus and Diagnostics Communication

P1921

No Bus Data From TRIONIC.










Fault Symptoms
No bus communication with the Trionic.

Diagnostic Help
Some of the following symptoms may be observable:
- DTC (P1622 in Trionic, if Trionic cannot be contacted)
- Misfiring
- Engine will not start

Check Wiring Harness.
Jiggle the wiring harness at several points and in different directions to detect intermittent breaks and short-circuits in the leads. Observe the multimeter, test lamp or diagnostic tool during the test.