Coolant temperature is detected by a water temperature sensor located at the heater unit. The A/C ECU uses coolant temperature to control the cold engine lockout function. The cold engine lockout function reduces blower speed until coolant temperature reaches the threshold value.
Air conditioner Control Module sets DTC B1203 if Water sensor has been detected below 0.1V for 4 seconds.
Item | Detecting Condition | Possible Cause |
DTC Strategy |
•
Voltage check |
•
Short in signal circuit
•
Faulty Water Sensor
•
Faulty A/C control Module |
Enable Conditions |
•
IG KEY ON | |
Threshold value |
•
Water temperature sensor has been dtected 0.1V for 4 seconds. | |
Failsafe |
•
Control with the value of 85℃(185℉). |
Temperature(℃/℉) | Resistance(㏀) | Temperature(℃/℉) | Resistance(㏀) |
-10/14 | 55.8 | 40/104 | 5.3 |
0/32 | 32.9 | 60/140 | 2.4 |
20/68 | 12.5 | 80/176 | 1.2 |
