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Home >> Porsche >> 1989 >> 928 CS V8-4957cc 5.0L >> Repair and Diagnosis >> Powertrain Management >> Computers and Control Systems >> Testing and Inspection >> Pinpoint Tests >> EZK Test Points (Ignition) >> Test Point 6 - Transmission Protection Switch
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Test Point 6 - Transmission Protection Switch

TEST POINT 6 - Transmission protection switch (automatic transmission only) - Fault code 2_25

Possible Causes, Elimination, Remarks
To protect the transmission shift elements, the ignition is retarded during transmission shifts.




If a fault is indicated here, connect the voltmeter to the socket sleeve side of terminals 1 and 2 at the 3-pin plug in the trunk well.

- Switch on the ignition. Display: approx. 5 V




Connect the ohmmeter to terminals 1 and 2 on the plug side

NOTE: The switch is checked with the engine running. Apply the handbrake and operate the foot brake. Comply with relevant safety regulations.

Display in position P or N: infinite resistance (switch open)
Display in position D: < 1 Ohm (switch closed).

If these values are not reached, measure directly at the switch or renew.
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