Signal Too High / Signal Missing
Signal too high / Signal missing
Checking the fan for the passenger compartment temperature sensor
- Ignition on.
Check using a hand that the fan for the passenger compartment temperature sensor is blowing.
If the fan is now working, the fault was caused by contact resistance or loose connections.
Is the fan working?
Yes - Checking the connectors and wiring
No - Checking the component and wiring
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Checking the connectors and wiring
- Ignition off
- Disconnect the connector for the climate control module (CCM)
- Disconnect the connector for the fan/passenger compartment temperature sensor.
Hint: If there is an open-circuit in the wiring for the power supply and ground, the climate control module (CCM) will not power the fan.
Check the power supply to the fan. Check for an intermittent open-circuit. Take a reading on the cable between climate control module (CCM) terminal #4 (#28) and fan terminal #4 (#24).
Check the ground lead for the fan. Check for an intermittent open-circuit. Take a reading on the fan connector between terminal #2 (#22) and chassis ground.
Check the connectors. Check for loose connections. Check for contact resistance. Check for oxidation.
Check the ground lead for the fan. Check for an intermittent short-circuit to supply voltage.
Take a reading on the fan connector between terminals #2 (#22) and #4 (#24).
Remedy as necessary.
Other information:
- For further information about the connectors, fuses and relays, see the Wiring Diagram
- Connecting the breakout box Connecting the Breakout Box, Climate Control Module (CCM)
- Signal description Signal Description, Climate Control Module (CCM)
- Component location Component Location, Climate Control Module (CCM)
- Climate control module (CCM) Service and Repair
- Checking wiring and terminals Checking Wiring and Terminals
Continue - Checking the component and wiring
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Checking the component and wiring
- Ignition off
- Disconnect the connector for the climate control module (CCM)
- Disconnect the connector for the fan/passenger compartment temperature sensor.
Hint: If there is an open-circuit in the wiring for the power supply and ground, the climate control module (CCM) will not power the fan.
Check the power supply to the fan. Check for an open-circuit. Take a reading on the cable between climate control module (CCM) terminal #4 (#28) and fan terminal #4 (#24).
Check the ground lead for the fan. Check for an open-circuit. Take a reading on the fan connector between terminal #2 (#22) and chassis ground.
Check the connectors. Check for loose connections. Check for contact resistance. Check for oxidation.
Check the ground lead for the fan. Check for a short-circuit to supply voltage.
Take a reading on the fan connector between terminals #2 (#22) and #4 (#24).
Remedy as necessary.
Other information:
- For further information about the connectors, fuses and relays, see the Wiring Diagram
- Connecting the breakout box Connecting the Breakout Box, Climate Control Module (CCM)
- Signal description Signal Description, Climate Control Module (CCM)
- Component location Component Location, Climate Control Module (CCM)
- Climate control module (CCM) Service and Repair
- Checking wiring and terminals Checking Wiring and Terminals
Continue - Verification
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Verification
Verification
Hint: After carrying out the repair, check that the fault has been remedied.
- Ignition off
- Reinstall the connectors, components etc.
- Ignition on.
Check by feeling with a hand that the fan is blowing.
Is the fan working?
Yes - VERIFIED
No - VERIFICATION FAILED
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VERIFIED - FAULT FOUND
VERIFICATION FAILED - Fault-tracing information
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Fault-tracing information
Attempt New Test - Checking the fan for the passenger compartment temperature sensor
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Information
Fault-tracing information
If the fault is intermittent, do not verify fault-tracing if the fault does not recur.
It is possible to view the information again, or leave fault-tracing for this diagnostic trouble code (DTC).
Do you want to view the information again?
Yes - Attempt New Test
No - FAULT FOUND
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Attempt New Test - Checking the fan for the passenger compartment temperature sensor
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