Procedure for testing the coolant temp sensor
06-13-2004, 02:20 AM
#3
Race Director
Easy way to do it is to unplug the DME box and measure the resistance of the coolant-temp sensor (with the car off). Do this test with a cold engine and then again when it's fully warmed up.
1. disconnect DME box
2. measure resistance between pin-17 (GND) and pin-13 (temp-sensor)
The resistances should read as follows:
32-F = 4.4 to 6.8 k-ohms
59-86F = 1.4 to 3.6 k-ohms
104F = 1.0 to 1.3 k-ohms
176F = 250 to 390 ohms
212 = 160 to 210 ohms
The temperature you want to use should be close to the temp. of the thermostat. So a hot engine would be around 180-degrees or so, putting the resistance between 200-300 ohms.
1. disconnect DME box
2. measure resistance between pin-17 (GND) and pin-13 (temp-sensor)
The resistances should read as follows:
32-F = 4.4 to 6.8 k-ohms
59-86F = 1.4 to 3.6 k-ohms
104F = 1.0 to 1.3 k-ohms
176F = 250 to 390 ohms
212 = 160 to 210 ohms
The temperature you want to use should be close to the temp. of the thermostat. So a hot engine would be around 180-degrees or so, putting the resistance between 200-300 ohms.
