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DTC P050D

DTC P050D:  Cold Start Idle Speed Problem

General Description 

GHH416739Courtesy of HONDA, U.S.A., INC.
GHH416740Courtesy of HONDA, U.S.A., INC.

The quick warm-up system supplies additional air and retards the ignition timing when the engine is cold to activate the catalytic converter as quickly as possible. When the actual engine speed is a specified fast idle value, and it continues for a specified time, the powertrain control module (PCM) detects a malfunction and stores a DTC.

Monitor Execution, Sequence, Duration, DTC Type 

Execution Once per driving cycle
Sequence None
Duration 5.0 seconds or more
DTC Type Two drive cycles, MIL on

Enable Conditions 

Condition Minimum Maximum
Elapsed time after starting the engine 4.0 seconds -
Engine coolant temperature [ECT Sensor 1] 14 deg.F (-10 deg.C) 176 deg.F (80 deg.C)
Throttle position Fully closed
Other Vehicle stopped

[ ]: HDS Parameter

Malfunction Threshold 

The engine speed [Engine Speed] is 2, 600 RPM or more 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.
  • Intake air duct breakage
  • Intake air duct misinstalled
  • Air cleaner breakage
  • Air cleaner damage
  • Air cleaner clogged
  • Mass airflow (MAF) sensor failure
  • Generator motor failure

Confirmation Procedure 

Operating Condition 

  1. Allow the engine to cool to an ambient engine coolant temperature [ECT Sensor 1] of 122 deg.F (50 deg.C) or less.
  2. Enter the maintenance mode, then start the engine, and let it idle for at least 10 seconds.

With the HDS 

None.

Diagnosis Details 

Conditions for setting the DTC 

When a malfunction is detected during the first drive cycle with the engine coolant temperature and intake air temperature at engine start-up within the specified temperature range, a Pending DTC is stored in the PCM memory. If the malfunction returns in the next (second) drive cycle with the engine coolant temperature and intake air temperature at engine start-up within the specified temperature range, 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 or by disconnecting the 12 volt battery.