Reading Actual Values
WARNING: This page is about a different car, the 2001 Mercedes-Benz SL500 and 2000 Mercedes-Benz SL500. However, it is still accessible from the selected car via links, so may be relevant.
NOTE:
A/C push button display will show "OP E", if an open circuit exists. Display will show "CL O", if a short circuit exists. Perform this actual value checking to aid in diagnosing a system malfunction.
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. Turn ignition on. Set temperature to 72°F. Press REST button for more than 6 seconds. A/C push button control unit will alternately display "01" and in-car temperature. Press blower motor speed increase button to display next value. See ACTUAL VALUES table. Press REST button to end test program.
ACTUAL VALUES
| Test Value (1) | Component/Value | Perform Test | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| 1 | In-Vehicle Temperature Sensor | (2)DTC B1226: IN-VEHICLE TEMPERATURE SENSOR | ||||||||
| 2 | Outside Temperature Sensor | (2)DTC B1422: SERIAL INTERFACE (K1) | ||||||||
| 3 | Left Heater Core Temperature Sensor | (2)DTC B1228: LEFT HEATER CORE TEMPERATURE SENSOR | ||||||||
| 5 | Evaporator Temperature Sensor | (2)DTC B1230: EVAPORATOR TEMPERATURE SENSOR | ||||||||
| 6 | Engine Coolant Temperature Sensor | (2)DTC B1422: SERIAL INTERFACE (K1) | ||||||||
| 7 | Refrigerant Pressure (06°4 = 6.4 Bar) | (2)DTC B1232: REFRIGERANT PRESSURE SENSOR | ||||||||
| 8 | Refrigerant Temperature Sensor (73°4 = 73.4°F) | (2)DTC B1233: REFRIGERANT TEMPERATURE SENSOR | ||||||||
| 10 | Blower Control Voltage (08°0-60°0 = 0.8-6.0 volts) | (3)BLOWER REGULATOR CONTROL | ||||||||
| 20 | Current For Auxiliary Fan in Milliamps (7 = 7 mA) | (2)DTC B1421: AUXILIARY FAN (AIR) CONTROL MODULE | ||||||||
| 21 | Engine Speed In RPM (00-99 = 0-9900 RPM) | (2)DTC B1422: SERIAL INTERFACE (K1) | ||||||||
| 22 | Vehicle Speed In Km/Hr | (2)DTC B1422: SERIAL INTERFACE (K1) | ||||||||
| 23 | (4) Battery Voltage At Terminal 58D | N/A | ||||||||
| 24 | Battery Voltage (12.5 = 12.5 Volts) | (3)A/C PUSH BUTTON CONTROL UNIT VOLTAGE SUPPLY (CIRCUIT 30) | ||||||||
| 40 & 41 | Hardware & Software Status | N/A | ||||||||
| 42 & 43 | Version Coding | N/A | ||||||||
| 52 | Selected Temperature Value | N/A | ||||||||
| 54 | A/C Compressor Emergency Shutoff | (2)DTC B1459: SERIAL INTERFACE (K2) | ||||||||
| 60 | Convertible Top Open (OPE) Or Closed (CLO) | (3)SOFT TOP ACTIVATION VOLTAGE | ||||||||
| 61 | Left Air Outlet Potentiometer Voltage | (2)DTC B1453: LEFT AIR OUTLET POTENTIOMETER | ||||||||
| 62 | Left Air Outlet Actuator Voltage | (2)DTC B1452: LEFT AIR OUTLET FEEDBACK POTENTIOMETER | ||||||||
| 63 | Center Air Outlet Potentiometer Voltage | (2)DTC B1454: CENTER AIR OUTLET POTENTIOMETER | ||||||||
| 64 | Center Air Outlet Actuator Voltage | (2)DTC B1457: CENTER AIR OUTLET FEEDBACK POTENTIOMETER | ||||||||
| 65 | Right Air Outlet Potentiometer Voltage | (3)RIGHT AIR OUTLET POTENTIOMETER | ||||||||
| 66 | Right Air Outlet Actuator Voltage | (2)DTC B1458: RIGHT AIR OUTLET FEEDBACK POTENTIOMETER | ||||||||
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