Measuring Value Blocks (Function 08)

Read Measuring Value Block - Function 08

NOTE:
- The various measuring value blocks are listed only for information. Perform the function "Read measuring value block" in Guided Fault Finding, here is also found a clarification of the corresponding measured values, specified permissible limit values and specifications as well as notes on the function of various components. Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.
- Component locations of activated components.
- Depending on position of the control motor, the various flaps are closed and opened over the adjustment range of the control motor via the installed lever. Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.

- If a value greater than "250" (open circuit or fault in Ground (GND) connection) or less than "5" (open circuit, fault in 5 V voltage supply or short circuit to GND connection) is displayed for one (or more) potentiometer(s) in one (or more) control motor(s), this indicates a malfunction in wire connection to control motor or in potentiometer of the or a control motor (same B+ supply or GND connection).
- If displayed value of a control motor is outside permitted range, check allocation of lever and curved washers which connect control motor shaft to flap(s).
- If no permissible value can be determined for a potentiometer in a control motor during the function "Basic Setting", display group corresponding to this control module displays a substitute value and stores a DTC in DTC memory. By using this substitute value (approx. average value in permissible tolerance range), the front Climatronic Control Module J255 (or Rear A/C Control Head (Climatronic) E265) controls the flap position when in emergency running mode.
- Depending on version of front A/C control head Climatronic Control Module J255 and Rear A/C Control Head (Climatronic) E265, "On" or "1" and "Off" or "0" may be displayed in measuring value block. If a display field is not assigned, no display or "not assigned" appears in this field.

Initiating the "Read measuring value block" function

- With ignition switched off, connect e.g. Vehicle Diagnosis, Testing and Information System VAS5051/5052 with Diagnostic Cable - 3 Meter VAS5051/5A to 16-pin Data Link Connector (DLC) in vehicle. Vehicle Diagnostic, Testing and Information System VAS5051/5052, Connecting and Selecting Functions
- Switch ignition on or start engine.
- Set the operating mode "Auto" at front Climatronic Control Module J255 (and at Rear A/C Control Head (Climatronic) E265).
- Select AC/Heating Electronics, front Climatronic Control Module J255 via address word "08" (or the Rear A/C Control Head (Climatronic) E265, optional equipment, via address word "28").
- Check DTC memory. Check DTC Memory (Function 02)
- Select function "08 - Read Measuring Value Block" for the respective control module.

The request to enter a display group appears on the display of Vehicle Diagnosis, Testing and Information System VAS5051/5052 (an input keypad appears).
- Via the input keyboard, enter the desired display group (e.g. "01" or "001" for "Display group number 001") and confirm by pressing the Q button.

Overview of selectable display group numbers:
- Front A/C control head Climatronic Control Module J255
- Rear A/C Control Head (Climatronic) E265
- Input desired display group number.

For example, the following appears on display of Vehicle Diagnosis, Testing and Information System VAS5051/5052 :
- In one display field, the selected display group appears.
- In one display field, the values of the four display fields are displayed:
- Value for display field "1" is displayed in the first row.
- Display of values for the corresponding display fields appear in the second, third and fourth rows.
- If a display field is not assigned, no display appears in this row or the message "not assigned" or "not installed" appears, no measured values are intended here.

Overview of display group numbers to be selected (of front A/C control head Climatronic Control Module J255)

Overview of display group numbers to be selected Rear A/C Control Head (Climatronic) E265

NOTE: Various values that are displayed in the measuring value blocks of Rear A/C Control Head (Climatronic) E265 are calculated by the front Climatronic Control Module J255 and transmitted via CAN-Bus system to the Rear A/C Control Head (Climatronic) E265 Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.