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Code B336 - Loss Of IPC Data: Notes

If BCM loses data communication with IPC and ignition is on, code B336 will be set. The problem is a result of 7-volt or ground fault to IPC or double open circuit in data communication line between IPC and BCM. If this failure occurs, cruise control will disengage (if engaged) and headlights (if on) will function on low beam.

NOTE: Test numbers refer to test numbers on diagnostic chart.
  1. Checks for an intermittent condition.
  2. Checks if problem is related to power and ground circuits or data communication line.
  3. Determines if data problem is due to IPC or wiring.
  4. Determines if fault is due to an open in circuit Nos. 800E and 800C or an internal IPC problem.
  5. Checks if fault is due to 7-volt power circuit or ground circuit from CPS.
  6. Checks ground circuit for an open, faulty IPC or a faulty CPS.