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DTC P1658

DTC P1658:  Electronic Throttle Control System (ETCS) Control Relay ON Malfunction

General Description 

GHH306858Courtesy of HONDA, U.S.A., INC.

The electronic throttle control system controls the throttle valve opening. The system includes the throttle actuator, the throttle valve, throttle position (TP) sensors A and B, the electronic throttle control system (ETCS) control relay circuit, the accelerator pedal position (APP) sensor, and the powertrain control module (PCM). When the accelerator pedal is pressed, the APP sensor detects the accelerator pedal opening value. The accelerator pedal opening value is converted to a signal in the APP sensor and transmitted to the PCM to compute the target position. The PCM determines the throttle valve target position according to the signal received and operates the throttle actuator to move the throttle valve to the target position. The actual throttle valve position is determined by TP sensors A and B (installed in the throttle body). When the voltage is applied from the ETCS control relay circuit to the IG1M terminal for a set time after the ETCS control relay circuit is turned off, the PCM detects a malfunction in the ETCS control relay circuit power switch and stores a DTC.

Monitor Execution, Sequence, Duration, DTC Type, OBD Status 

Execution Once per driving cycle
Sequence None
Duration 2.0 seconds or more
DTC Type One drive cycle, MIL on

Enable Conditions 

Condition  
Vehicle OFF (LOCK) mode

Malfunction Threshold 

The communication signal is input from the PCM for at least 2.0 seconds after the ETCS control relay circuit is turned off.

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.

Diagnosis Details 

Conditions for setting the DTC 

When a malfunction is detected, the MIL comes on and a Pending DTC, a Confirmed DTC, and the freeze data are stored in the PCM memory.

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 or by disconnecting the 12 volt battery.