CKT Test ECTF - Cooling Fan Engine Coolant Temp Sensor

Fig 1: Identifying ECTF Connector Terminals (2.0L A/T)

NOTE: Enter this test only when a Code 69 is displayed during self-test procedures (KOEO or KOER) or when directed here from another circuit test. This test is intended to diagnose ECTF circuit only.

CIRCUIT PIN IDENTIFICATION (ECTF)

Circuit	Breakout Box Pin No.	PCM Pin	Wire Color
ECTF	50	2K	Blue/White
SIG RTN	46	3D	Black/Blue

1) Check System Integrity Visually check all wiring, connectors and components for evidence of damage, shorting or looseness. If a fault is found, repair as necessary. If no fault is found, go to next step.

2) Check ECTF Sensor Resistance Run engine until engine coolant reaches specified temperature. See RESISTANCE SPECIFICATIONS (ECTF SENSOR) table. Monitor temperature at ECTF sensor using Rotunda Digital Thermometer (055-00100). Turn ignition off. Leaving PCM disconnected, install breakout box. Measure resistance between ECTF and SIG RTN test terminals at breakout box. Compare readings with RESISTANCE SPECIFICATIONS (ECTF SENSOR) table. If resistance is not as specified, go to next step. If resistance is as specified, ECTF circuit is okay. If no other problem or code is found, replace PCM.

RESISTANCE SPECIFICATIONS

Temperature °F (°C)	Ohms
196 (91)	1700-1840
207 (97)	1420-1530
226 (108)	1030-1110

3) Check ECTF Circuit Turn ignition off. With breakout box installed and PCM disconnected, disconnect ECTF sensor connector. Measure and record resistance between ECTF test pin at breakout box and ECTF terminal at ECTF sensor connector. Measure and record resistance between ground and ECTF test pin at breakout box. If resistance between ECTF test pin at breakout box and ECTF terminal at ECTF sensor connector is less than 5 ohms and resistance between ground and ECTF test pin at breakout box is 10,000 ohms, go to step 4). If resistance is not as specified, repair ECTF wire between ECTF sensor connector and PCM.

4) Check SIG RTN Circuit (2.0L A/T) Ensure ignition is off and ECTF sensor is disconnected. With breakout box installed and PCM disconnected, measure resistance between SIG RTN test pin at breakout box and SIG RTN terminal at ECTF sensor connector. If resistance is less than 5 ohms, replace ECTF sensor. If resistance is 5 ohms or more, repair SIG RTN wire between ECTF sensor connector and PCM.