DTC 42-1: Differential Fluid Temperature Sensor (Short to Power)

WARNING: This page is about a different car, the 2013 Acura MDX, 2012 Acura MDX, 2011 Acura MDX, and 2010 Acura MDX. However, it is still accessible from the selected car via links, so may be relevant.

NOTE:

Before you troubleshoot, review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION ).
If the vehicle was driven prior to this troubleshooting procedure, allow the rear differential to cool for more than an hour before continuing.

Turn the ignition switch to ON (II).
Clear the DTC with the HDS.
Turn the ignition switch to LOCK (0), then turn the ignition switch back to ON (II).
Check for DTCs with the HDS.
Is DTC 42-1 indicated?

YES -Go to step 5.

NO -Intermittent failure, the system is OK at this time.
Turn the ignition switch to LOCK (0).
Disconnect the rear differential fluid temperature sensor 2P connector.
Turn the ignition switch to ON (II).
Check the REAR DIFFERENTIAL FLUID TEMPERATURE SENSOR in the DATA LIST with the HDS.
Is the sensor reading 0 V?

YES -Replace the rear differential fluid temperature sensor (see REAR DIFFERENTIAL FLUID TEMPERATURE SENSOR REPLACEMENT ).

NO -Go to step 9.
Turn the ignition switch to LOCK (0).
Disconnect SH-AWD control unit connector A (20P).
Check for continuity between rear differential fluid temperature sensor 2P connector terminals No. 1 and No. 2.

Fig 1: Checking Continuity Between Rear Differential Fluid Temperature Sensor 2P Connector Terminals No. 1 And No. 2
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?

YES -Repair a short in the wires between rear differential fluid temperature sensor 2P connector terminals No. 1 and No. 2.

NO -Go to step 12.
Turn the ignition switch to ON (II).
Measure the voltage between body ground and rear differential fluid temperature sensor 2P connector terminals No. 1 and No. 2 respectively.

Fig 2: Measuring Voltage Between Body Ground And Rear Differential Fluid Temperature Sensor 2P Connector Terminals No. 1 And No. 2
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there about 5V or more?

YES -Repair a short to power in the wire harness.

NO -Update the SH-AWD control unit if it does not have the latest software (see SH-AWD® CONTROL UNIT UPDATE ), or substitute a known-good SH-AWD control unit (see SH-AWD® CONTROL UNIT REPLACEMENT ), and recheck. If the symptom/indication goes away with the updated SH-AWD control unit, troubleshooting is complete. If the symptom/indication goes away with a known-good SH-AWD control unit, replace the original SH-AWD control unit (see SH-AWD® CONTROL UNIT REPLACEMENT ).