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A/T - Erratic Shift Opertion in OVERDRIVE

89mazda04

Category Applicable Model/s
7 1988-1989 323
Subject Bulletin No. 063/89
ATX ERRATIC O.D. OPERATION Issued 6/6/89
Revised
DESCRIPTION

Because of poor sealing of the thermostat, engine coolant temperature fails to rise to the normal operating temperature, causing the erratic shift operation in O.D. gear as mentioned below.

1) Vehicle will not shift into O.D.
2) Vehicle shifts into and out of O.D. at random.

As shown in the table below, O.D. shift operation is related to "ON/OFF" conditions of the water temperature switch. This problem happens if the coolant temperature does not rise to the normal operating temperature or fluctuates around it.

If you encounter a customer complaint about the above symptoms [1) or 2)], you are requested to check whether or not poor sealing of the thermostat is observed.

WATER TEMP. WATER TEMP. SW. O.D. OPERATION

Under 60~C (149~F) ON (Closed) No O.D.

60-72~C (149-162~F) ON or OFF O.D. or no O.D.

Over 72~C (162~F) OFF (Open) O.D. only