Signal Too Low
Signal too low
Diagnostic trouble code (DTC) status, ECM-2000 Engine coolant temperature (ECT) sensor. Signal too low
Reading off diagnostic trouble code (DTC) status ECM-2000
Note! When reading off the diagnostic trouble code (DTC) status, other stored diagnostic trouble codes (DTCs) and their status will be listed.
- Read off the diagnostic trouble code (DTC) status. Check the status of the relevant diagnostic trouble code (DTC).
Was the status of the relevant diagnostic trouble code (DTC) permanent?
Yes - Checking the wiring and component
No - Intermittent fault
-------------------------------------------------
Intermittent fault
Signal too low. Intermittent fault
Checking wiring and connectors
Check the signal cable between control module terminal #A40 and engine coolant temperature (ECT) sensor terminal 2. Check for an intermittent short-circuit to ground.
Other information
- To access the control module, see Engine control module (ECM), replacing Service and Repair
- To connect the breakout box, see Connecting the breakout box Connecting the Breakout Box
- To access or replace the engine coolant temperature (ECT) sensor, see Engine coolant temperature (ECT) sensor, replacing Service and Repair
- For information about signals see Signal specification Signal Description / Specification
- Checking wiring and terminals Checking Wiring And Terminals.
Continue - Fault-tracing information
------------------------
Fault-tracing information
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
------------------------
Attempt New Test - Checking wiring and connectors
FAULT FOUND - DONE
DONE - DONE
-------------------------------------------------
DONE - DONE
-------------------------------------------------
Checking the wiring and component
Check the resistance of the engine coolant temperature (ECT) sensor. For the resistance values, see Engine coolant temperature (ECT) sensor Specifications.
Check the signal cable between control module connector terminal #A40 (#A40) and engine coolant temperature (ECT) sensor terminal 1. Check for an short-circuit to ground. Check for an open-circuit.
Check the ground lead between control module connector terminal #A61 (#B3) and engine coolant temperature (ECT) sensor connector terminal 2. Check for an open-circuit.
Remedy as necessary.
Other information
- To connect the breakout box, see Connecting the breakout box Connecting the Breakout Box
- To access or replace the engine coolant temperature (ECT) sensor, see Engine coolant temperature (ECT) sensor, replacing Service and Repair
- For information about signals see Signal specification Signal Description / Specification
- Checking wiring and terminals Checking Wiring And Terminals.
Continue - Verification
-------------------------------------------------
Verification
Verification
Hint: After carrying out the repair, check that the fault has been remedied.
- Ignition off.
- Reconnect connectors, reinstall components.
- Start the engine and let it idle.
- Read off engine coolant temperature (ECT) sensor signal.
Compare the engine coolant temperature (ECT) sensor signal with the table value according to: Engine coolant temperature (ECT) sensor Specifications.
Let the engine run at idling speed, check that the signal sinks when the engine warms up.
Is the engine coolant temperature (ECT) sensor signal OK?
Yes - VERIFIED
No - VERIFICATION FAILED
------------------------
VERIFICATION FAILED - Fault-tracing information
VERIFIED - Fault Found
-------------------------------------------------
Fault-tracing information
Information
Fault-tracing information
The fault should have been detected and remedied. As this is not the case fault-tracing has failed.
Exit fault-tracing for this diagnostic trouble code (DTC) or make another attempt.
Do you want to exit fault-tracing?
Yes - FAULT-TRACING FAILED
No - Attempt New Test
------------------------
FAULT-TRACING FAILED - FAULT-TRACING FAILED
Attempt New Test - ECM-2000 Engine coolant temperature (ECT) sensor. Signal too low
-------------------------------------------------