ECU - No Interchangeability Between New and Old Unit
90mazda03 Applicable Model/s 1988-89 626/MX-6Subject INTERCHANGEABILITY OF E.G.I. CONTROL UNIT (E.C.U.)
Bulletin No. 001/90
Issued 2/14/90
Revised
DESCRIPTION
Since the December, 1988 production, the material used for some of the terminals of the connector between the E.C.U. and the engine harness has been changed from gold to tin. In accordance with this design change, there is no interchangeability between new and old parts regarding the E.C.U. and the engine harness.
If a new E.C.U. is installed using an old engine harness, although the system itself will operate normally, galvanic corrosion may occur due to the different materials of the terminal plating. The corrosion at the terminals may result in poor driveability.
Thus, when you replace an E.C.U. or an engine harness, please be sure to check the generation of the parts and use a replacement part of the same generation.
NOTE:
To identify new and old parts, the color of the E.C.U. connectors and the engine harness has been changed from yellow to white at the time of the design change. When replacing an E.C.U. or an engine harness, check the color of the connector first and choose appropriate parts.
Yellow: Old E.C.U. and engine harness
White: New E.C.U. and engine harness
VIN OF PRODUCTION CHANGE
626/MX-6 w/o Turbo
Produced in Japan: JM1GD * * * * K1737082 December 1, 1988
Produced in the U.S.A.: 1YVGD * * * * K5223617 January 18, 1989
IMPORTANT:
This bulletin replaces Service Bulletin Category 4, no. 060/89. Please reference this bulletin when using your 1989 Service Bulletin file.