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DTC Troubleshooting: P16BB

DTC P16BB:
 Alternator B Terminal Circuit Low Voltage
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 HDS.
  1. Start the engine.
  1. Check under these conditions:
    • A/C on
    • Temperature control at maximum cool
    • Blower fan at maximum speed
    • Rear window defogger on
    • Headlights on high beam
  1. Hold the engine speed at 2,000 rpm (min −1 ) (A/T in P or N, M/T in neutral) for 1 minute.
  1. Check for Temporary DTCs or DTCs with the HDS.
Is DTC P16BB indicated?
YES -
Go to Step 7 .
NO -
Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the alternator and the battery terminal fuse box, and check the battery performance.
  1. Check for poor connections or loose terminals at the alternator and the battery terminal fuse box (+B line).
Are the connections and terminals OK?
YES -
Go to Step 8 .
NO -
Repair the connectors or terminals, then go to Step 9 .
  1. Check for an open in the wire between the alternator and battery terminal fuse box at the engine wire harness.
Is the harness OK?
YES -
NO -
Repair open in the wire between the alternator and the battery terminal fuse box, then go to Step 9 .
  1. Turn the ignition switch to ON (II).
  1. Reset the ECM/PCM with the HDS.
  1. Start the engine.
  1. Check under these conditions:
    • A/C on
    • Temperature control at maximum cool
    • Blower fan at maximum speed
    • Rear window defogger on
    • Headlights on high beam
  1. Hold the engine speed at 2,000 rpm (min −1 ) (A/T in P or N, M/T in neutral) for 1 minute.
  1. Check for Temporary DTCs or DTCs with the HDS.
Is DTC P16BB indicated?
YES -
Check for poor connections or loose terminals at the alternator and the battery terminal fuse box, 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.■