DTC Indicator Light L: An Open Or Short In The Mode Control Motor Circuit

Test the mode control motor (see MODE CONTROL MOTOR TEST ).
Is the mode control motor OK?
1. YES - Go to step 2.
2. NO - Replace the mode control motor.
Disconnect the mode control motor 7P connector.
Disconnect climate control unit connector B (30P), and gauge assembly connector A (30P).
Check for continuity between body ground and climate control unit connector B (30P) terminals No. 3, 4, 5, 6, 7, 8, and 9 individually.

Fig 1: Checking For Continuity Between Body Ground & Climate Control Unit Connector B (30P) Terminals
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?
1. YES - Repair any short to body ground in the wire(s) between the climate control unit, the gauge assembly, and the mode control motor.
2. NO - Go to step 5.
Turn the ignition switch ON (II), and check the same terminals for voltage.

Fig 2: Checking For Voltage Between Body Ground & Climate Control Unit Connector B (30P) Terminals
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there any voltage?
1. YES - Repair any short to power in the wire(s) between the climate control unit, the gauge assembly, and the mode control motor. This short may also damage the climate control unit. Repair the short to power before replacing the climate control unit.
2. NO - Go to step 6.

Turn the ignition switch OFF, and check for continuity between following terminals of climate control unit connector B (30P) and the mode control motor 7P connector.

CLIMATE CONTROL UNIT CONNECTOR-TO-MODE CONTROL MOTOR CONNECTOR CONTINUITY CHART

Climate Control Unit Connector B (30P) Terminal	Mode Control Motor 7P Connector Terminal
No. 3	No. 7
No. 4	No. 3
No. 5	No. 4
No. 6	No. 5
No. 7	No. 6
No. 8	No. 1
No. 9	No. 2

Fig 3: Checking For Continuity Between Terminals Of Climate Control Unit Connector B (30P) & The Mode Control Motor 7P Connector

Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?

YES - Check for loose wires or poor connections at climate control unit connector B (30P) and at the mode control motor 7P connector. If the connections are good, substitute a known-good mode control motor, and recheck. If the symptom/indication goes away, replace the original mode control motor. If the symptom/indication continues, substitute a known-good climate control unit, and recheck. If the symptom/indication goes away, replace the original climate control unit.
NO - Repair any open in the wire(s) between the climate control unit and the mode control motor.