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DTC Troubleshooting: P15B8

DTC P15B8:
 Starter Control System High Input
NOTE: Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information.
  1. Turn the ignition switch to ON (II).
  1. Clear the DTC with the HDS.
  1. Turn the ignition switch to LOCK (0).
  1. Turn the ignition switch to ON (II), and wait 5 seconds.
  1. Check for Temporary DTCs or DTCs with the HDS.
Is DTC P15B8 indicated?
YES -
Go to Step 6 .
NO -
Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the TCM and the ECM.■
  1. Turn the ignition switch to LOCK (0).
  1. Jump the SCS line with the HDS.
  1. Disconnect ECM connector A (49P).
  1. Turn the ignition switch to ON (II).
  1. Measure the voltage between ECM connector terminal A43 and body ground.
Is there voltage?
YES -
Substitute a known-good TCM, then go to Step 14 . If DTC P15B8 is not indicated, replace the original TCM, then go to Step 14 .
NO -
Go to Step 11 .
  1. Turn the ignition switch to LOCK (0).

  1. Check for continuity between ECM connector terminal A43 and TCM connector A (37P) terminal No. 10.
Is there continuity?
YES -
Go to Step 22 .
NO -
Repair open in the wire between the ECM (A43) and the TCM, then go to Step 14 .
  1. Turn the ignition switch to LOCK (0).
  1. Reconnect all connectors.
  1. Turn the ignition switch to ON (II).
  1. Reset the ECM with the HDS.
  1. Turn the ignition switch to LOCK (0).
  1. Turn the ignition switch to ON (II), and wait 5 seconds.
  1. Check for Temporary DTCs or DTCs with the HDS.
Is DTC P15B8 indicated?
YES -
Check for poor connections or loose terminals at the TCM and the ECM, then go to Step 1 .
NO -
Troubleshooting is complete. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.■
  1. Reconnect all connectors.
  1. Turn the ignition switch to LOCK (0).
  1. Turn the ignition switch to ON (II), and wait 5 seconds.
  1. Check for Temporary DTCs or DTCs with the HDS.
Is DTC P15B8 indicated?
YES -
Check for poor connections or loose terminals at the TCM and the ECM. If the ECM was updated, substitute a known-good ECM, then recheck. If the ECM was substituted, go to Step 1 .
NO -
If the ECM was updated, troubleshooting is complete. If the ECM was substituted, replace the original ECM. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.■