Signal Too Low

Signal too low

Checking the evaporator temperature




- Ignition on.
Check that the evaporator temperature is within its permitted range. If the climate control system has not been running and the engine has cooled down, the temperature must be the same as the outside temperature.
The fault is intermittent if the outside temperature is now correct.
Read off the evaporator temperature by clicking on the VCT2000 symbol.





Are the temperatures correct?

Yes - Checking the wiring

No - Checking the component and wiring

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Checking the wiring




- Ignition off
- Disconnect the connector for the climate control module (CCM).
Check the signal cable between the climate control module (CCM) and the evaporator temperature sensor. Check for an intermittent short-circuit to ground.
Take a reading on the connector for the climate control module (CCM) between terminals #5 (#29) and #16 (#40).
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).
Check the signal cable between the climate control module (CCM) and the evaporator temperature sensor. Check for a short-circuit to ground.
Take a reading on the connector for the climate control module (CCM) between terminals #5 (#29) and #16 (#40).
Check the connectors for contact resistance and oxidation.
Check that the climate control module (CCM) is receiving a correct value from the evaporator temperature sensor by measuring its resistance and comparing with the values in the table.
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
- Component resistance values [1][2]Electrical Specifications





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 the evaporator temperature sensor by clicking the VCT2000 symbol.
Check that the value from the evaporator temperature sensor corresponds to the ambient temperature.





Does the status change?

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 evaporator temperature

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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 evaporator temperature

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