P1822
Symptom: CHECK GEARBOX warning lamp on.
TCM in Limp-Home mode.
Output RPM. No Signal.
Fault symptoms
CHECK GEARBOX warning lamp on.
TCM in Limp-Home mode.
Conditions
No signal from the output shaft speed sensor when:
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Car speed is higher than 4 km/h.
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Selector lever position sensor in position D, 3, 2 or 1.
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Fluid temperature higher than 20°C.
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Diagnostic help
A reading of the output shaft speed can be obtained with the diagnostic instrument.
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Select "
Data Display / Output Control (New)"
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"
Vehicle Speed (Output RPM)"
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Compare the diagnostic instrument reading with the speedometer when driving the car.
Check the wiring
Jiggle the wiring harness at several points and in different directions to reveal intermittent breaks and short circuits in the various leads. Observe the multimeter, test lamp or diagnostic instrument while carrying out this check.
Diagnostic procedure
1 Check the speed sensor ground connection
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Unplug the 2-pin speed sensor connector.
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Connect a test lamp between B+ and pin 2 (yellow lead) in the 2-pin female connector.
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The test lamp should light up.
All OK?
Continue fault diagnosis with step 2.
Rectify the relevant lead and continue with step 3, final check.
2 Check the control module input for the output shaft speed.
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Measure the resistance between pin 2 and the 2-pin female connector. The resistance should be 6.0-6.6 kOhm.
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All OK?
Change the speed sensor and continue with step 3, final check.
Rectify the relevant lead between speed sensor pin 1 and control module pin 30 and continue with step 3, final check.
3 Final check
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Clear all diagnostic trouble codes in the system.
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Perform a driving cycle:
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Drive the car at varying loads and engine speeds for 5 minutes.
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Evaluate the driving cycle:
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Make sure the trouble code has not recurred.
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Has the trouble code recurred?
Continue with “
Diagnostic procedure before replacing control module
”
The steps taken to rectify the fault were correct.
