P1790
Symptom: No downshifting for fast acceleration
Kick-down switch, shorted to ground.
Fault symptom
No downshifting for fast acceleration
Condition
Shorting to ground at the same time as the throttle position is less than 70%% for at least 2 seconds.
Diagnostic help
A reading of the kickdown switch status can be obtained with the diagnostics instrument. Select "READ ON/OFF". Select "KICKDOWN SWITCH". With the accelerator fully depressed, i.e. in the kickdown position, the diagnostics instrument will show ON, otherwise OFF.
Diagnostic procedure
1 Check the transmission control module's signal input
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Unplug the kick-down switch connector.
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Connect the Scan tool diagnostics instrument.
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Turn the ignition switch to the ON position.
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Select ""KICKDOWN SWITCH".
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Read the diagnostics instrument with
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connector pin 1 open "OFF"
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connector pin 1 connected to a good grounding point "ON"
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Is the diagnostics instrument reading correct?
Continue with point 3.
Rectify the lead (including connector) between the kickdown switch connector pin 1 and the control module pin 8 and continue with step 2.
2 Check the kick-down switch's connection to ground
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Turn the ignition switch to the ON position.
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Connect a test lamp to pins 1 and 2 of the connector. The lamp should light up.
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Did the test lamp light up?
Adjust or, if necessary, replace the kick-down switch and continue with point 3.
Rectify the lead (including connector) between the kickdown switch connector pin 2 and grounding point G4, and continue with step 3.
3 Final check
Clear the diagnostic trouble code, drive the car on test at varying engine loads and speeds for 5 minutes and obtain readouts of any diagnostic trouble codes that are generated.
Does the diagnostic trouble code recur?
Continue with
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The remedial action taken was correct.
