DTC B2965: Rear Communication Failure

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.

Clear the DTCs with the HDS.
Turn the ignition switch to LOCK (0) and then back to ON (II).
Do the self-diagnostic function with the HDS (see HOW TO USE THE SELF-DIAGNOSTIC FUNCTION WITH THE HDS ).
Check for DTCs.
Is DTC B2965 indicated?

YES -Go to step 5.

NO -Intermittent failure, check for loose wires or poor connections in the rear climate control panel and climate control unit circuit.
Turn the ignition switch to LOCK (0).
Disconnect the rear climate control panel 10P connector.
Turn the ignition switch to ON (II).
Measure the voltage between rear climate control panel 10P connector terminal No. 1 and body ground.

Fig 1: Measuring Voltage Between Rear Climate Control Panel 10P Connector Terminal No. 1 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there battery voltage?

YES -Go to step 9.

NO -Repair an open in the wire between the No. 30 (10 A) fuse in the under-dash fuse/relay box and rear climate control panel.
Turn the ignition switch to LOCK (0).
Check for continuity between rear climate control panel 10P connector terminal No. 3 and body ground.

Fig 2: Checking For Continuity Between Rear Climate Control Panel 10P Connector Terminal No. 3 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?

YES -Go to step 11.

NO -Check for an open in the wire between the rear climate control panel and body ground. If the wire is OK, check for poor ground at G506 (see CONNECTOR TO FUSE/RELAY BOX INDEX ).
Disconnect climate control unit connector B (14P).
Check for continuity between the following terminals of climate control unit connector B (14P) and the rear climate control panel 10P connector.
14P:

No. 11

No. 12

10P:

No. 10

No. 9

Fig 3: Checking For Continuity Between Following Terminals Of Climate Control Unit Connector B (14P) And Rear Climate Control Panel 10P Connector
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?

YES -Go to step 13.

NO -Repair an open in the wire(s) between the climate control unit and the rear climate control panel.
Check for continuity between body ground and climate control unit connector B (14P) terminals No. 11 and No. 12 individually.

Fig 4: Checking For Continuity Between Body Ground And Climate Control Unit Connector B (14P) Terminals No. 11 And No. 12
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?

YES -Repair a short to body ground in the wire(s) between the climate control unit and the rear climate control panel.

NO -Go to step 14.
Check for continuity between climate control unit connector B (14P) terminals No. 11 and No. 12.

Fig 5: Checking For Continuity Between Climate Control Unit Connector B (14P) Terminals No. 11 And No. 12
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?

YES -Repair a short in the wires between the climate control unit and the rear climate control panel.

NO -Substitute a known-good rear climate control panel, and recheck. If the symptom/indication goes away, replace the original rear climate control panel (see REAR CLIMATE CONTROL PANEL REMOVAL/INSTALLATION ).