DTC Troubleshooting: B2982 (K and AUTO)
DTC B2982 or DTC indicator K and AUTO:
Heater Control Unit Lost Communication with Each Control Motor
  1. Clear the DTC with the HDS.
  1. Turn the ignition switch OFF and then ON (II).
  1. Check for DTCs.
Is DTC B2982 or K and AUTO indicated?
YES -
Go to Step 5 .
NO -
Intermittent failure, check for loose wires or poor connections on the heater control unit and each control motor circuit.■
  1. Turn the ignition switch OFF.
  1. Disconnect the heater control unit 32P connector.
  1. Check for continuity between body ground and the heater control unit 32P connector terminals No. 25 and No. 26 individually.
Is there continuity?
YES -
Go to Step 8 .
NO -
Go to Step 10 .
  1. Disconnect the A/C wire harness from the dashboard wire harness.
  1. Check the same terminals for continuity to body ground
Is there continuity?
YES -
Repair short in the wire(s) between the heater control unit and the dashboard wire harness 12P connector.■
NO -
Repair the short in the A/C wire harness.■
  1. Disconnect the A/C wire harness 12P connector from the dashboard wire harness.
  1. Check for continuity between the following terminals of the heater control unit 32P connector and the dashboard wire harness 12P connector.
    32P:
    12P:
    No. 25
    No. 10
    No. 26
    No. 9
    No. 27
    No. 8

Is there continuity?
YES -
Go to Step 12 .
NO -
Repair open in the wire(s) between the heater control unit and the dashboard wire harness 12P connector.■
  1. Check for continuity between the heater control unit 32P connector terminals as follows.
    From terminal
    To terminals
    25
    26, 27
    26
    27

Is there continuity between any of terminals?
YES -
Repair the short in the wires.■
NO -
Go to Step 13 .
  1. Reconnect the A/C wire harness 12P connector to the dashboard wire harness.
  1. Check the same terminals for continuity between the heater control unit 32P connector terminals.
Is there continuity between any of terminals?
YES -
Repair the short in the A/C wire harness.■
NO -
Go to Step 15 .
  1. Reconnect the heater control unit 32P connector.
  1. Turn the ignition switch ON (II).
  1. Measure the voltage between the heater control unit 32P connector terminals No. 25 and No. 27.
Is there battery voltage?
YES -
Replace the A/C wire harness. If DTC B2982 indicates again, substitute a known-good heater control unit, and recheck. If the symptom/indication goes away, replace the original heater control unit.■
NO -
Substitute a known-good heater control unit, and recheck. If the symptom/indication goes away, replace the original heater control unit .■