DTC P1D99

WARNING: This page is about a different variant/trim than selected.

DTC P1D99: PCU Electric Coolant Pump

General Description

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

The power control unit (PCU) controls the PCU electric coolant pump according to the rotational speed of the PCU electric coolant pump calculated from the frequency (duty fixed to 50 %) detected from the NEWP terminal. If the detection duty of the NEWP terminal (NEWPDUTY) is out of a specified value for a specified time, the motor control module in the PCU detects a malfunction and stores a DTC.

Monitor Execution, Sequence, Duration, DTC Type

Execution	Continuous
Sequence	None
Duration	5.0 seconds or more
DTC Type	Two drive cycles, MIL on, POWER SYSTEM indicator on

Enable Conditions

Condition	Minimum	Maximum
12 volt battery voltage	10 V	-
Vehicle	ON mode

Malfunction Threshold

If the detection duty of the NEWP terminal is 100 % or more or 0 % for at least 5.0 seconds.

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.

PCU electric coolant pump NEWP line open
PCU electric coolant pump NEWP line short to ground
PCU electric coolant pump relay IG PCU EWP line open
PCU electric coolant pump relay failure
PCU electric coolant pump failure
PCU internal failure

Confirmation Procedure

Operating Condition

Turn the vehicle to the ON mode.

With the HDS

Select the ELECTRIC WATER PUMP TEST in the Electric Powertrain FUNCTION TEST with the HDS. Then do the START.

Diagnosis Details

Conditions for setting the DTC

When a malfunction is detected during the first drive cycle, a Pending DTC is stored in the motor control module memory. If the malfunction returns in the next (second) drive cycle, the MIL comes on and a Confirmed DTC and the freeze data are stored.

Conditions for clearing the DTC

The MIL is cleared if the malfunction does not return in three consecutive trips in which the diagnostic runs. The MIL, the Pending DTC, the Confirmed DTC, and the freeze data can be cleared with the scan tool Clear command.