P1790
Symptom: No downshifting when accelerating quickly.
Kickdown switch, short circuit to ground
Fault symptoms
No downshifting when accelerating quickly.
Conditions
Short circuit to ground while throttle position is less than 70%% for at least 2 seconds.
Diagnostic help
The status of the kick-down switch can be read with the diagnostic tool. Select "READ ON/OFF". Select "KICK-DOWN SWITCH". When the accelerator pedal is fully depressed, i.e. kick-down, ON will be displayed, otherwise OFF.
Diagnostic procedure
1 Check the control module signal input
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Unplug the kickdown switch connector.
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Connect the diagnostic tool.
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Turn the ignition to the ON position.
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Select "KICK-DOWN SWITCH".
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Read off the diagnostic tool 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 diagnostic tool reading correct?
Continue with step 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 kickdown switch ground connection
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Turn the ignition to the ON position.
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Connect a test lamp between connector pins 1 and 2. The lamp should light up.
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Is the lamp alight?
Adjust or, if necessary, replace the kickdown switch and continue with step 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.
