B0608 Power Moding Error

DTC B0608 Power Moding Error:

DTC B0608 Power Moding Error (Part 1 Of 3):

DTC B0608 Power Moding Error (Part 2 Of 3):

DTC B0608 Power Moding Error (Part 3 Of 3):

CIRCUIT DESCRIPTION
The Body Control Module (BCM) receives voltage inputs from three ignition signals. The BCM receives voltage from the IGN0 Fuse when ignition switch is in OFF/UNLOCK, RUN or START positions. The BCM receives voltage from the PCM-BCM Fuse in RUN or START and from the CRANK SIGNAL Fuse when in START. If the BCM sees any of the following conditions a DTC code is set:
^ If IGN1 is active and IGN0 is inactive.
^ If CRANK is active and IGN0 is inactive.
^ If CRANK is active and IGN1 is inactive.

CONDITIONS FOR SETTING THE DTC
^ The BCM does not detect voltage from IGN0 when in RUN or START but the BCM detects voltage from IGN1 when in RUN or START.
^ The BCM detects voltage in CRANK when in START but the BCM does not detect voltage from IGN0 when in START.
^ The BCM detects voltage in CRANK when in START but the BCM does not detect voltage from IGN1 when in START
^ All conditions must be present for more than 0.3 seconds.

ACTION TAKEN WHEN THE DTC SETS
^ Stores a DTC B0608 in the BCM memory.
^ No driver warning message will be displayed for this DTC.
^ The current DTC clears when the fault is no longer present.

CONDITIONS FOR CLEARING THE DTC
^ The BCM no longer detects an open or short to B+.
^ A history DTC will clear after 100 consecutive ignition cycles if the condition for the malfunction is no longer present.
^ Using a scan tool.

DIAGNOSTIC AIDS
^ The following conditions may cause an intermittent malfunction to occur:
- An intermittent open or short to voltage in circuit 439, 806 or 1500.
- Poor connections at the BCM, or the fuse block.
- The BCM is always detecting B+ from one or more of these three inputs.
- The BCM is never recognizing B+. DTC P1626 will set in the Powertrain Control Module (PCM) when the ignition switch is in the RUN position with the BCM disconnected.

TEST DESCRIPTION
Numbers below refer to the step numbers on the diagnostic table.
1. Always perform the BCM Diagnostic System Check before attempting to diagnose a DTC B0608.
2. Determines if the BCM receives voltage when the ignition switch is cycled.
3. Checks for a short to B+ in circuit 806.
4. Determines if the ignition switch is bad or a poor connection or an open in circuit 1500.
6. Determines if there is a short to B+ in circuit 439.
9. Determines if there is a short to B+ in circuit 439 between the UH Electrical Center and the fuse block.
10. Checks for an open in circuit 439.
12. Determines if there is a short to B+ in circuit 439 between the BCM and the UH Electrical Center.
13. Clears all BCM DTCs and checks for BCM DTC B0608 again.
14. Determines if there is an open in circuit 439 between the Underhood Electrical Center and the Fuse Block.
18. Determines if the open is in the UH Electrical Center or in circuit 439 between the UH electrical center and the BCM.