Page 27 of 91

01-21
      
Notes:  
     
1997   If A/C control head -E87- is unable to 
determine the duration of time when ignition is 
off ("standing time"), DTC 01206 "signal for time 
span ignition off" is loaded into memory. The 
A/C control head will then default to a standing 
time greater than 4 hours. The actual measured 
values of the outside temperature sensor are 
then used as instantaneous outside and engine 
temperature inputs for A/C system control. 
When the "heating" mode is selected under 
these conditions, fresh air blower -V2- has a 
delayed start (even when the actual standing 
time is less than 4 hours and the engine is 
warm)  page 01
-86
 , Read Measuring Value 
Block. The outside air temperature display -
G106- may also indicate incorrect outside 
temperature values. 
     
If both display fields of the A/C control head do 
not light with ignition switched on check control 
head coding   Page 01
-57
 . 
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        Page 28 of 91

01-22
 Diagnostic Trouble Code (DTC) table
 
Notes:  
 
DTC changes affecting m.y. 1997   vehicles   page 01
-38
 .
 Diagnostic Trouble Codes (DTC) recognized by A/C control head -E87- and displayed on VAG1551 Scan Tool (ST)   
starting on page 01
-24
 . 
 If malfunctions occur only occasionally or if the DTC memory was not erased after repairs, such DTC are displayed as 
"sporadic faults." (The contents of DTC memory is retained until erased, "permanent memory"). 
 DTCs and flash codes (only for specific components) appear only in the printout in operating mode -1-, (Rapid data 
transfer). 
 In addition to displayed DTC and affected component descriptions, malfunction cause information is listed in the table 
below the DTC code. 
 After performing repairs and operating the A/C system, DTC memory must always be checked again to confirm the repair.
 Before replacing a suspected malfunctioning component, check all appropriate wiring, connections, harness connectors 
and Ground (GND) connections. 
 When checking for the cause of sporadic faults, check all plug connections and wiring between A/C control head -E87- 
and any component recognized as being inoperative using wiring diagram. 
 After replacing AC/heating system components, always perform basic setting (function 04), check DTC memory (function 
Pa
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        Page 55 of 91

01-40
 
VAG1551 scan tool 
display  Possible cause  
Corrective action  
01206  
Signal for time span 
ignition off1) 
 
implausible 
signal /SP  - Short or open circuit in wiring/connections 
between instrument cluster and -E87- 
- Instrument cluster malfunctioning.- Diagnose and repair short or open circuit in 
wiring using wiring diagram. 
- Check signal from instrument cluster using 
function 08, Read measuring value block 
 page 01
-86
 . 
01274 4131  
Air Flow Flap Motor -
V71- 2) 
 
blocked or no 
current /SP  - Short or open circuit in wiring/connections 
between -V71- and -E87-. 
- Air flap or fresh/recirculated air flap 
binding/sticking 
- -V71- malfunctioning.- Diagnose and repair short or open circuit in 
wiring using wiring diagram. 
- Check air flap or fresh/recirculated air flap for 
ease of movement. 
- Check -V71- using function 03, Output 
Diagnostic Test Mode (DTM)   page 01
-42
 . 
1) If A/C control head -E87- is unable to determine the duration of time when ignition is off ("standing time"), DTC 01206 
"signal for time span ignition off" is loaded into memory. The A/C control head will then default to a standing time greater than 
4 hours. The actual measured values of the outside temperature sensor are then used as instantaneous outside and engine 
temperature inputs for A/C system control. When the "heating" mode is selected under these conditions, the fresh air blower -
V2- has a delayed start (even when the actual standing time is less than 4 hours and the engine is warm)   page 01
-86
 , 
Read measuring value block. The outside air temperature display -G106- may also indicate incorrect outside temperature 
values.  
2) -V71- operates the air flow flap as well as the fresh/recirculated air flap.  
Pa
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        Page 61 of 91
01-44
      
Starting output Diagnostic Test Mode (DTM)  
     
-  Start engine, switch on compressor (press 
"Auto" button), adjust air flow to center 
instrument panel outlets only. 
     
-  Connect Scan Tool VAG1551 or 1552 in 
operating mode -1-, enter address word 08 "A/C 
Heating Electronics" and move forward in 
program until "select function XX" appears in the 
display. 
     
-  Switch on printer by pressing the PRINT button 
(indicator lamp in button comes on). 
     
-  Check DTC memory   page 01
-18
 .
     
-  Note any stored DTCs for reference and move 
forward in program until "select function XX" 
appears in the display. Rapid data transfer 
HELP
Select function XX
    
Indicated on display (function selection)  
-  Press buttons -0- and -3-. 
Rapid data transfer 
Q
03 - Output Dia
gnostic Test Mode
    
Indicated on display  
-  Press -Q- button to confirm input.
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        Page 73 of 91
01-52
      
Basic setting (function 04)
 
     
-  Connect Scan Tool VAG1551 or 1552, enter 
address word 08 "A/C Heating Electronics" and 
move forward in program until "select function 
XX" appears in the display. 
     
-  Switch on printer by pressing the PRINT button 
(indicator lamp in the button comes on). 
     
-  Check DTC memory (   page 01
-18
) and repair 
all malfunctions which are displayed. 
     
-  Erase DTC memory   page 01
-55
 .
     
- Check coding (   page 01
-57
 ) and re-code if 
necessary. 
Rapid data transfer 
HELP
Select function XX
    
Indicated on display (function selection)  
-  Press buttons -0- and -4-.
Rapid data transfer 
Q
04 - Basic Settin
g
    
Indicated on display  
-  Press -Q- button to confirm input.
Start basic settin
g 
HELP
Input display number XXX
    
Indicated on display  
-  Press buttons -0- and -1-.
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        Page 82 of 91
head and execute basic setting. 
     
-  Connect Scan Tool VAG1551 or 1552 in 
operating mode -1-, enter address word 08 "A/C 
Heating Electronics" and move forward in 
program until "select function XX" appears in the 
display. 
     
-  Switch on printer by pressing the PRINT button 
(indicator lamp in button comes on). 
Pa
ge 82 of 91 A/C s
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pair&id=AUDI.B5.HA01.01.1