Engine Controls - MIL ON/DTC's P0128/P1486 Stored
01-022November 23, 2005
Applies To:
2000 Accord L4 - ALL
MIL Comes On With DTC P0128 or DTC P1486
(Supersedes 01-022, dated September 30, 2003, to update the information indicated by asterisks)
SYMPTOM
The MIL is on with DTC P0128 (thermostat range/ performance problem) or DTC P1486 (cooling system malfunction).
PROBABLE CAUSE
*The ECM/PCM calculates an anticipated engine coolant temperature (ECT) during cold start. If the anticipated temperature is significantly higher than the actual ECT reading, DTC P0128 or P1486 will be set.*
However, some very specific driving/ambient temperature conditions can cause the ECM/PCM to set DTC P0128 or P1486 when there isn't a problem with the vehicle.
CORRECTIVE ACTION
Replace the ECM/PCM. The replacement ECM/PCMs have revised software.
WARRANTY CLAIM INFORMATION
In warranty:
The normal warranty applies.
Failed Part: P/N 37820-PAA-L80
H/C 6286421
Defect Code: 072
Symptom Code: C99
Skill Level: Repair Technician
Out of warranty:
Any repair performed after warranty expiration may be eligible for goodwill consideration by the District Parts and Service Manager or your Zone Office. You must request consideration, and get a decision, before starting work.
PARTS INFORMATION
DIAGNOSIS
Connect the Honda Diagnostic System (HDS) to the DLC (data link connector), and check for DTCs.
^ If DTC P0128 or DTC P1486 is stored, go to REPAIR PROCEDURE.
^ If another DTC is stored, go to the appropriate troubleshooting procedure in the service manual.
REPAIR PROCEDURE
1. Write down the part number of the current ECM/PCM. The part number is on the label at the front of the ECM/PCM.
2. Match the part number you wrote down with the current ECM/PCM part number listed under PARTS INFORMATION, then get the correct replacement ECM/PCM.
3. Download the immobilizer key transponder codes from the PCM to the HDS. Refer to REPLACING THE ECM/PCM in service bulletin 00-049, Immobilizer System (Type 2).
4. Remove the ECM/PCM.
5. Replace the ECM/PCM in the reverse order of removal.
6. Upload the immobilizer key transponder codes from the HDS to the PCM. Refer to REPLACING THE ECM/PCM in service bulletin 00-049, Immobilizer System (Type 2).
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