Sensor Value Check
WARNING: This page is about a different car, the 1999 Mercedes-Benz CLK430, 1999 Mercedes-Benz CLK320, and 1998 Mercedes-Benz CLK320. However, it is still accessible from the selected car via links, so may be relevant.
Temperature display areas in A/C push-button control unit will display (in sequence) temperature sensor readings, refrigerant pressure, fan control voltage, software and control module version. This is useful in checking the tolerance range of temperature sensors and refrigerant pressure. Temperature control is maintained during test. Sensor values can be checked using the HHT. The following steps are for the A/C push-button control unit:
- Turn ignition on.
- Set both temperature selectors to 72°F.
- Press REST button for at least 6 seconds.
- Numeral "1" and temperature will alternately appear in left display area.
- Press left AUTO button to display next value. See SENSOR VALUE TEST CODES table.
- Press REST button to end test program.
NOTE:
Display will show "- 40" if there is a short or open circuit. Negative sensor values will be shown on the left display as "-".
SENSOR VALUE TEST CODES
| Test Value On A/C |
HHT Reading |
System Affected |
| 01 |
01 |
In-Vehicle Temperature Sensor |
| 02 |
02 |
Outside Temperature Sensor |
| 03 |
03 |
Left Heater Core Temperature Sensor |
| 04 |
04 |
Right Heater Core Temperature Sensor |
| 05 |
06 |
Evaporator Temperature Sensor |
| 06 |
05 |
Coolant Temperature Sensor (Climate Control) |
| 07 |
07 |
Refrigerant Pressure (06 = 6 Bar) |
| 08 |
08 |
Refrigerant Temperature Sensor |
| 09 |
|
Menu For Activations |
| 10 |
13 |
Blower Control Voltage (08.0 Min, 60.0 Max) |
| 20 |
|
Current For Auxiliary Fan In Milliamps |
| 21 |
12 |
Engine Speed In RPM |
| 22 |
11 |
Vehicle Speed In K/Hr |
| 23 |
14 |
Battery Voltage At Terminal 58D In Percent |
| 24 |
|
Battery Voltage |
| 40 |
|
Software Status |
| 41 |
|
Hardware Status |
| 42 |
|
Version Code No. 1 |
| 43 |
|
Version Code No. 2 |