John Deere 523848.05 – ATC (Automatic Temperature Control) / ETC: Air Flow Mode Motor Circuit Current Low

The control unit measures an excessively low amperage (current) at the connecting leads of the adjusting motor (B132), indicating that the circuit is either open or shorted. The control unit restricts or disables the air distribution control to prevent damage.

• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R
• 6020 to 6920S
• 6120 to 6420
• 6120L to 6520L
• 6230
• 6330
• 6430
• 7720
• 7820
• 7920
• 8120 to 8520
• 8230T
• 8330T
• 8430T
• 8245R-8400R
• 8310RT-8360RT
• 9230
• 9330
• 9430
• 9530
• 9630
• 9470RT
• 9520RT
• 9570RT

1. 1

   Restart the engine to verify if the active service code reappears, as a system reset can sometimes clear communication faults

2. 2

   Access the adjusting motor for air distribution (B132) and visually inspect for physical damage, dirt, or mechanical binding in the flap control mode

3. 3

   Inspect the electrical connectors at the motor and the ATC/ETC module for bad, loose, widened, slid-back, or corroded contacts

4. 4

   Use a multimeter to check the wiring harness (specifically connecting leads 2028/2029 or 928/929 to the motor) for open circuits, shorts, or damaged insulation

5. 5

   Measure the current flow at the motor leads to ensure it is within the specified range

1. 1

   Power Down

   Turn off the engine and place the tractor in park.

2. 2

   Access the Motor

   Locate the Air Flow Mode Motor (Adjusting Motor for Air Distribution) within the cab's HVAC/evaporator housing.

3. 3

   Repair Wiring

   If the diagnostic checks revealed broken wires or corroded connectors, recondition the sub-assemblies, connectors, or contacts as required.

4. 4

   Replace the Motor

   If the wiring is intact but the motor is malfunctioning or not drawing the expected current, remove the faulty B132 adjusting motor and install a replacement.

5. 5

   Calibrate the System

   After installing the new motor, calibrate the adjusting motor for air distribution through the CommandCenter display or service tool using the ATC diagnostic addresses (e.g., Address ATC023).

6. 6

   Clear Codes and Test

   Delete the stored diagnostic trouble code and perform an operational check of the air distribution system manually to ensure the flaps move correctly without restriction.