DTC Indicator C: An Open In The Outside Air Temperature Sensor Circuit

WARNING: This page is about a different car, the 2006 Acura MDX, 2005 Acura MDX, 2004 Acura MDX, and 2003 Acura MDX. However, it is still accessible from the selected car via links, so may be relevant.

Remove the outside air temperature sensor (see OUTSIDE AIR TEMPERATURE SENSOR TEST ) and test it (see OUTSIDE AIR TEMPERATURE SENSOR TEST ).
Does the outside air temperature sensor test OK?
1. YES - Go to step 2.
2. NO - Replace the outside air temperature sensor.
Disconnect climate control unit connector B (26P).
Check for continuity between the No. 18 terminal of climate control unit connector B (26P) and the No. 1 terminal of the outside air temperature sensor 2P connector.

Fig 1: Checking For Continuity Between No. 18 Terminal Of Climate Control Unit Connector B
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?
1. YES - Go to step 4.
2. NO - Repair open in the wire between the climate control unit and the outside air temperature sensor.
Check for continuity between the No. 1 terminal of climate control unit connector B (26P) and the No. 2 terminal of the outside air temperature sensor 2P connector.

Fig 2: Checking For Continuity Between No. 1 Terminal Of Climate Control Unit Connector B
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?
1. YES - Check for loose wires or poor connections at climate control unit connector B (26P) and at the outside air temperature sensor 2P connector. 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 - Repair open in the wire between the climate control unit and the outside air temperature sensor.