MIL Is On With “Unknown” DTC

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A03-077
October 24, 2003

Applies To: 2001–02 Civic DX, HX, LX, and EX – ALL

SYMPTOM

The MIL is on, and when you try to retrieve the DTC with the HDS, “Unknown” is displayed.

PROBABLE CAUSE

The ECM/PCM software does not properly communicate the DTC to the HDS. When this happens, “Unknown” is displayed on the HDS screen.

CORRECTIVE ACTION

Use the Honda Interface Module (with September 2003 or later software) to update the ECM/PCM.

WARRANTY CLAIM INFORMATION

In warranty: The normal warranty applies.

Operation Number: 123503

Flat Rate Time:	0.3 hour
Failed Part:	P/N 37820-PLR-L55 H/C 7064371
Defect Code:	03214
Symptom Code:	03203
Template ID:	03-077A
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.

REPAIR PROCEDURE

If not already done, load the September 2003 or later iN (Interactive Network) CD onto the iN master terminal. Loading instructions are included in the CD’s mailing.
Update the ECM/PCM with the Honda Interface Module (HIM). For instructions, refer to Service Bulletin 01-023, Using the Honda Interface Module to Update Control Units/Modules.
Check if the MIL comes on:
- If the MIL comes on, retrieve the DTC(s), and do the appropriate troubleshooting.
- If the MIL stays off, return the vehicle to the customer.