Hypertech Chip or coolant temp switch is loosing its mind
Thread Starter
Team Owner
Joined: Jan 2003
Posts: 20,322
Likes: 248
From: Summerland B.C. Canada
Hypertech Chip or coolant temp switch is loosing its mind
The other day my main fan had a brain fart and decided to take some time off. Well today it's working but it comes on at 174 rather than 160 degrees normally. Whats up with that?
Anyone have similar problems in the past?
Thanks Again
Dan :smash: :smash:
:cheers:
Anyone have similar problems in the past?
Thanks Again
Dan :smash: :smash:
:cheers:
Drifting
Joined: Mar 2001
Posts: 1,636
Likes: 3
From: Lafayette IN
Re: Hypertech Chip or coolant temp switch is loosing its mind (AGENT 86)
I am going to gander that your main fan is still being controlled by the ECM.
The backup switch in the cylinder head won't complete the circuit until you are into the 2's.
The coolant sensor that feeds the ECM is a different sensor/sender than the one that feeds the Digidash, so really either could be off. Also, the back-up switch completes the trio of coolant-related sensors on your car.
But my only question is this: If your fan normally comes on at 160*F, when the heck does it turn off? Unless you are always above ~35 MPH, that thing is going to be on all the time...
The backup switch in the cylinder head won't complete the circuit until you are into the 2's.
The coolant sensor that feeds the ECM is a different sensor/sender than the one that feeds the Digidash, so really either could be off. Also, the back-up switch completes the trio of coolant-related sensors on your car.
But my only question is this: If your fan normally comes on at 160*F, when the heck does it turn off? Unless you are always above ~35 MPH, that thing is going to be on all the time...
Burning Brakes
Joined: Feb 2003
Posts: 1,212
Likes: 0
From: OH
Re: Hypertech Chip or coolant temp switch is loosing its mind (AGENT 86)
The other day my main fan had a brain fart and decided to take some time off. Well today it's working but it comes on at 174 rather than 160 degrees normally. Whats up with that?
Anyone have similar problems in the past?
Thanks Again
Dan :smash: :smash:
:cheers:
Anyone have similar problems in the past?
Thanks Again
Dan :smash: :smash:
:cheers:
Pro
Joined: Jul 2002
Posts: 729
Likes: 4
From: Yukon OK
Re: Hypertech Chip or coolant temp switch is loosing its mind (rsafier)
I may have to go review my theory of operation for an 85 Vette, but I seem to recall that the fan is controlled by a sensor on the head and the engine temp indicator is on the front of the manifold. The Hypertech chip with the lower temp does not control the fan, but the chip allows the ECM to go into closed loop at a lower temp. If you used the lower temp thermostat without the chip the ECM would wait for the engine to get up to operating temp and it would never get there. Don't recall if that condition times out or not. Anyway I think your problem is the fan sensor not the ECM/chip.
Or you could do what some of us have done. My fan is wired to be on all the time. Also run the Hypertech chip.
Or you could do what some of us have done. My fan is wired to be on all the time. Also run the Hypertech chip.
