Signal Too Low - Intermittent Fault

ECM-2000 ENGINE COOLANT TEMPERATURE (ECT) SENSOR
SIGNAL TOO LOW - INTERMITTENT FAULT

Checking wiring and connectors




WARNING!
Before fault-tracing can begin, the engine cooling fan (FC) relay connector must be disconnected to prevent the engine cooling fan (FC) engaging. Diagnostic trouble code (DTC) ECM-6110 Engine cooling fan (FC) low-speed signal may be stored. After fault-tracing the connector must be reconnected.

Check signal cable between control module #A4 (#A4) and engine coolant temperature (ECT) sensor #1 for an intermittent open-circuit according to [1][2]Checking Wiring and Terminals. Intermittent Faults and an intermittent short-circuit to supply voltage according to [1][2]Checking Wiring and Terminals. Intermittent Faults

Hint: With the ignition on and engine coolant temperature (ECT) sensor connector disconnected the voltage between #1 and ground terminal should be approximately 5 V.

Check ground lead between control module #A60 (#A60) and engine coolant temperature (ECT) sensor #2 for an intermittent open-circuit according to [1][2]Checking Wiring and Terminals. Intermittent Faults

Other information
- Connecting the breakout box/accessing the control module, Connecting the Breakout Box (ECM)
- To access the engine coolant temperature (ECT) sensor, Engine Temperature Sensor, Replacing
- For resistance values, see Component Specifications. Specifications
- For information about signals, see Diagnostic Parameters and Pinout Values. Signal Description, ME7, B5XX4T


Fault-tracing information
If the fault is intermittent, do not verify fault-tracing if the fault does not recur.