Does P0118 mean the engine is actually cold?

No — it means the PCM is reading the engine as impossibly cold because the ECT signal voltage is too high, usually from an open circuit or a failed sensor, not because the engine is genuinely that cold.

What's the difference between P0118 and P0117?

P0118 is signal voltage too high (circuit high / open). P0117 is the opposite — signal voltage too low (circuit low / shorted to ground), which the PCM reads as impossibly hot.

Why is my throttle/ETC light on with P0118?

On equipped Grand Cherokees the PCM links the ETC warning to this fault. It typically clears once the coolant temperature reading is corrected and the code is reset.

Can a loose connector cause P0118?

Yes. A loose or corroded ECT connector creates an intermittent open, which spikes the signal voltage and sets the code — so the connector is one of the first things to inspect.

P0118 Jeep Grand Cherokee – Engine Coolant Temperature Sensor Circuit High

P000A Bank 1 Camshaft 1 Position Slow Response (3.6l)
P000B Bank 1 Camshaft 2 Position Slow Response (3.6l)
P000C Bank 2 Camshaft 1 Position Slow Response (3.6l)
P000D Bank 2 Camshaft 2 Position Slow Response (3.6l)
P0010 Bank 1 Camshaft 1 Position Actuator Circuit Open
P0013 Bank 1 Camshaft 2 Position Actuator Circuit Open
P0014 Bank 1 Camshaft 2 Position Target Performance (5.7l)
P0016 Crankshaft/camshaft Timing Misalignment - Bank 1 Sensor 1

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