Climate Control Power and Ground Circuit Troubleshooting

Are the fuses OK? 

1. YES  - Go to step 2.
2. NO  - Replace the fuse(s), and recheck.

Fig 1: Measuring Voltage Between No. 2 Terminal Of Climate Control Unit Connector A (12P) And Body Ground

Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there battery voltage? 

1. YES  - Go to step 5.
2. NO  - Repair open in the wire between the No. 16 (7.5 A) fuse in the under-dash fuse/relay box and the climate control unit.

Fig 2: Measuring Voltage Between No. 3 Terminal Of Climate Control Unit Connector A (12P) And Body Ground

Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there battery voltage? 

1. YES  - Go to step 7.
2. NO  - Repair open in the wire between the No. 18 (7.5 A) fuse in the under-dash fuse/relay box and the climate control unit.

Fig 3: Checking Continuity Between No. 10 Terminal Of Climate Control Unit Connector A (12P) And Body Ground

Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity? 

1. YES  - Check for loose wires or poor connections at climate control unit connector A (12P). If the connections are good, substitute a known-good climate control unit, and recheck. If the symptom/indication goes away, replace the original climate control unit.
2. NO  - Check for an open in the wire between the climate control unit and body ground. If the wire is OK, check for poor ground at G404.