DTC P0116: Low Coolant Temperature Or Specified Value: Condition

WARNING: This page is about a different car, the 2002 Suzuki Esteem. However, it is still accessible from the selected car via links, so may be relevant.

DTC is set when engine coolant temperature fails to reach predetermined level after vehicle has been running for a predetermined time. Engine coolant temperature variation is less than predetermined. MIL is illuminated when Engine Control Module (ECM) detects malfunction during 2 consecutive drive cycles. Possible causes are:

ECT sensor malfunction.
ECT sensor circuit malfunction.
Thermostat malfunction.
ECM malfunction.