- Mar 28, 2010
- 2
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Ok here's my situation that I have struggling for a year now
I have a 97 Mustang GT 4.6 SOHC
1) When the a/c is switched on the Engine cooling fan turns on at low speed
(cable Red Orange) instead of turning at high speed.
2) If I don't turn on the a/c, the fan will not turn on and the engine will overheat
(this has already caused me to replaced the intake manifold)
What I have done:
a) If I disconnect the Engine coolant temperature sensor the fan turn's on at High speed
This shows that the fan (at high speed), the HDEF relay (in the CCRM), the fuses that feed the system work and that at least the PCM is able to detect an open circuit in the temperature sensor circuit.
Temperature Sensor internal resistance does decrease as engine gets hotter.
b) Have replaced the Engine coolant temperature sensor (right sensor)
c) Have replaced the Constant Control Relay module
And the result is still the same
Has anyone have any ideas?
I have a 97 Mustang GT 4.6 SOHC
1) When the a/c is switched on the Engine cooling fan turns on at low speed
(cable Red Orange) instead of turning at high speed.
2) If I don't turn on the a/c, the fan will not turn on and the engine will overheat
(this has already caused me to replaced the intake manifold)
What I have done:
a) If I disconnect the Engine coolant temperature sensor the fan turn's on at High speed
This shows that the fan (at high speed), the HDEF relay (in the CCRM), the fuses that feed the system work and that at least the PCM is able to detect an open circuit in the temperature sensor circuit.
Temperature Sensor internal resistance does decrease as engine gets hotter.
b) Have replaced the Engine coolant temperature sensor (right sensor)
c) Have replaced the Constant Control Relay module
And the result is still the same
Has anyone have any ideas?