
Diagnostic procedure

No.8 does not shift to fourth gear (4gr)Mazda 6 Service Manual: Oil pressure switch removal/installation
Warning
When the transaxle and ATF are hot, they can badly burn. Turn off
the engine and wait untill they are cool before replacing ATF.
1. Disconnect the negative battery cable.
2. Remove the under cover.
3. Disconnect the cord assembly connector.
4. Remove the oil pressure switch.
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Mazda 6 Service Manual: Intermittent concern troubleshooting
Vibration Method
If malfunction occurs or becomes worse while driving on a rough road or
when engine is vibrating, perform the steps below.
Note
There are several reasons why vehicle or engine vibration could
cause an electrical malfunction. Some of the things to check for:
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