ECM - Non Interchangeability

Group: ENGINE ELECTRICAL

Number: 01-36-016

Date: JULY, 2001

Model: 2001 V6 SANTA FE, 1999-2001 V6 SONATA

Subject
2001 V6 SANTA FE & 1999-2001 V6 SONATA
ECM NON-INTERCHANGEABILITY

DESCRIPTION:

While working on a 2001 V6 Santa Fe or 1999-2001 V6 Sonata, care must be taken when exchanging an engine control module (ECM) for diagnostic purposes.

When an ECM is exchanged from another vehicle (For example, a "lot car"), the vehicle's specification MUST be the same for the following:

1. Transmission (ATM or MTM)

2. Brake System (ABS or Non-ABS)

3. Model Year

If an ECM is exchanged from a different specification vehicle, a check engine light and Diagnostic Trouble Code (DTC) can be falsely set.

NOTE:
Having the same ECM part number is NOT sufficient information:

1) The ECM part number will be the same whether the vehicle has ABS or not.

2) The ECM part number will be the same whether the vehicle has ATM or not.

EXPLANATION:

When a "new" ECM (one that has never been installed in a vehicle before) is installed in a vehicle, the ECM "learns" whether the vehicle has ABS and ATM. Once this information is learned, the ECM expects and processes the related information accordingly. This learning cannot be reversed, even when the power to the ECM is disrupted.

EXAMPLE:

2001 V6 Santa Fe with ABS:

If an ECM from a non-ABS 2001 V6 Santa Fe is swapped into this vehicle, code P0500 (VEHICLE SPEED SENSOR MALFUNCTION) will be set, and the check engine light will illuminate (after test driving).