DTC Advanced Diagnostics: P1D7B (343), P1D7B (343) (Traction Motor Control Module)

DTC P1D7B (343):  Reactor Over Temperature (Traction Motor Control Module Detected)DTC P1D7B (343):  Reactor Over Temperature (Generator Motor Control Module Detected)

General Description 

Courtesy of HONDA, U.S.A., INC.

The cooling for the inverter is performed by the motor control module which monitors coolant temperature and the temperature of the parts on the coolant circuit, drives the DT electric water pump, and sends a drive command of the DT radiator fan to the powertrain control module (PCM). If the reactor temperature in the inverter exceeds a specified value for a set time, the motor control module detects a malfunction and stores a DTC.

Monitor Execution, Sequence, Duration, DTC Type 

Enable Conditions 

Malfunction Threshold 

The reactor temperature exceeds 315 deg.F (157 deg.C) for at least 1.0 second.

Possible Cause 

NOTE:  The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.

• Cooling problem (coolant leakage, coolant passage clogged)
• Reactor temperature sensor 1 failure
• Reactor temperature sensor 2 failure
• DT radiator fan failure
• DT electric water pump failure
• Motor control module failure

Diagnosis Details 

Conditions for setting the DTC 

When a malfunction is detected, the MIL, the POWER SYSTEM indicator, and the 12 volt battery charging system indicator comes on and a Pending DTC, a Confirmed DTC, and the freeze data are stored in the motor control module memory.

Conditions for clearing the DTC 

The MIL, the POWER SYSTEM indicator, and the 12 volt battery charging system indicator are cleared if the malfunction does not return in three consecutive trips in which the diagnostic runs. The MIL, the POWER SYSTEM indicator, the 12 volt battery charging system indicator, the Pending DTC, the Confirmed DTC, and the freeze data can be cleared with the scan tool Clear command or by disconnecting the 12 volt battery.