
01-34
 
 DTC 01270 continued 
VAG1551 scan 
tool display  Possible cause  
Corrective action  
01270 4121  
A/C Clutch N251) 
  
Speed difference 
too great /SP3) 
 
 
 
 
 
 
 
 
 
 
 
  
Continued on 
next page.  - Ribbed belt loose, slipping
 
 
 
- A/C control head -E87- not coded correctly
- Loose terminal or contact resistance in circuit between 
-N25- and A/C clutch relay -J44- or in wiring/connections 
between -G111-2)4) and -E87- 
- N25 slipping 
- Incorrect crankshaft vibration damper (diameter)
- Malfunction in refrigerant circuit (compressor not 
operating freely). - Check belt tension   Repair Manual, 
Engine Mechanical, Repair Group 13 
Compare speeds of engine and compressor 
using function 08 (Read measuring value 
block)  page 01
-63
  
- Code A/C control head -E87- according to 
compressor type installed4) "Zexel" or 
"Nippondenso"  page 01
-57
  
- Diagnose and repair circuit using wiring 
diagram and perform electrical tests 
 page 01
-115
 
- -G111-, -J44- electrical test   page 01
-
115
  
- Repair or replace -N25-   page 87
-85
- Check for proper vibration damper part 
number 
- Check compressor for free operation and 
replace if necessary   page 87
-38
 
1/2) Continued from   page 01
-33
  
3) If speed difference is 30 % to 60 %, A/C Clutch is switched on again by -E87- for not more than 9 times during a driving 
period (ignition off). If speed difference is greater than 60 %, A/C Clutch remains off until engine is started again. 
Pa
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01-35
 
 DTC 01270 continued 
VAG1551 scan tool 
display  Possible cause  
Corrective action  
01270 4121  
A/C Clutch N251) 
  
Mechanical 
malfunction /SP2)   - Belt and coupling pulley of -N25- are stuck together
- Short circuit to positive in wiring/connections between -
N25- and for A/C Clutch relay -J44- 
- -J44- malfunction
- Short circuit to ground in wiring/connections between -E87- 
and -J44- - Repair or replace -N25-   
page 87
-85
  
 
- Diagnose and repair short 
circuit using 
wiring diagram 
 
- Replace -J44-
- Diagnose and repair short 
circuit using 
wiring diagram. 
01271 4122  
Temperature Regulator 
Flap Motor V68 
  
Blocks or de-energized 
/SP  - Short circuit, open circuit or incorrect terminal assignment 
(wires interchanged) of connectors between -V68- and -E87-
- Temperature flap sticking
- -V68- malfunction- Diagnose and repair short 
circuit, open 
circuit or confirm terminal 
assignment using wiring 
diagram 
- Check for free operation of 
temperature flap 
- Test -V68- using function 03 
(Output DTM) 
 page 01
-42
 
Pa
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ystem, On Board Dia
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)
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01-36
 
VAG1551 scan tool 
display  Possible cause  
Corrective action  
01272 4123  
Central Air Flap 
Motor -V70- 
  
Blocks or de-
energized /SP  - Short circuit, open circuit in wiring or incorrect terminal 
assignment (wires interchanged) of connectors between -
V70- and -E87- 
- Central flap sticking
- -V70- malfunction- Diagnose and repair short circuit, 
open 
circuit or confirm terminal assignment 
using wiring diagram 
- Check for free operation of central 
flap 
- Test -V70- using function 03 (Output 
DTM) 
 page 01
-42
 
01273 4124  
Fresh air blower V2 
  
Control 
difference /SP  - Short circuit or open circuit in wiring between V2, control 
module for fresh air blower J126 and/or -E87- 
- Open circuit in voltage supply or ground connection to -
J126- 
- -J126- malfunction
- -V2- mechanical malfunction.- Diagnose and repair short circuit or 
open circuit in wiring using wiring 
diagram 
 
- Diagnose and repair open circuit 
using  
wiring diagram 
- -J126- electrical test   page 01
-115
 - Replace -V2-
01274 4131  
Air flow flap motor 
V71 
  - Short circuit, open circuit in wiring or incorrect terminal 
assignment (wires interchanged) of connectors between 
V71 and -E87- 
- Air flow flap sticking- Diagnose and repair short circuit, 
open 
circuit or confirm terminal assignment 
using wiring diagram 
Pa
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)
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01-37
 
VAG1551 Scan Tool display  
Possible cause  
Corrective action  
01582           
Coolant Temperature Signal  
Short circuit or open circuit between 
instrument cluster and A/C control head -
E87- - Locate short circuit or open circuit 
according to wiring diagram and repair 
   Short circuit to 
Ground /SP  
Open/Short circuit 
to B+ /SP  
Incorrect 
Signal /SP  Instrument cluster malfunctioning- Check signal from instrument cluster.
Note:  
The DTC "Coolant Temperature Signal" is only recognized by A/C control heads -E87- with one display. 
Pa
ge 50 of 91 A/C s
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gnostic 
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)
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01-38
 Diagnostic Trouble Code (DTC) table, changes specific to vehicles 1997 
 
Notes:  
The following DTCs are no longer recognized beginning m.y. 1997: 
 
00529 Speed info missing (sensor -G111- deleted).
 00799 A/C engine coolant temperature (ECT) sensor -G110- (sensor deleted).
 00801 A/C refrigerant high pressure switch -F118- (switch deleted).
 01270 A/C clutch -N25- (Sensor -G111- deleted).
The following DTCs are new for 1997, or are current DTCs with additional references to 1997 changes. DTCs and component 
references include various malfuction causes in the display below the DTC, etc. 
VAG1551 scan tool display  
Possible cause  
Corrective action  
00604  
Back Pressure Flap Motor 
Position Sensor -G113- in Air 
Flow Flap Motor -V71-1) 
  
Short circuit to ground /SP  
Open circuit/short circuit to 
positive /SP  - Short circuit, open circuit in wiring or incorrect 
terminal assignment (wires interchanged) of 
connectors between -G113- and -E87- 
- Air flow flap not operating freely
- -G113- in -V71- inoperative- Diagnose and repair short circuit, 
open circuit in wiring or confirm 
terminal assignment using wiring 
diagram 
 
- Check for free operation of air flow 
flap3) 
- Replace -V71-
Pa
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01-39
 
VAG1551 scan tool 
display  Possible cause  
Corrective action  
00792 3224  
A/C Pressure Switch 
-F129- 
 
Short circuit to 
ground /SP  - Open circuit in wiring/connections between -F129- 
and -E87- 
- Malfunction in operation of coolant fan -V7- (stage 1) 
 
 
- Condenser or radiator dirty.
- Malfunction in operation of coolant fan -V7- (stage 2) 
by A/C pressure switch -F129- 
- -F129- malfunction
- Excess or low refrigerant system pressure- Diagnose and repair short or open circuit 
in wiring using wiring diagram. 
- Test fan operation -V7- (stage 1) using 
function 03 (Output DTM) 
 page 01
-42
 
- -V7- electrical test
 page 01
-115
 . 
- Clean condenser and radiator.
- Test -V7- (stage 2) via A/C pressure 
switch -F129-   page 87
-67
 ). 
- Test -F129-   page 87
-67
 .
- Check refrigerant system pressures
 page 87
-192
 . 
Notes:  
 
A/C pressure switch -F129- contains 2 switching elements. Via terminals 1 & 2, the compressor is shut off due to low or 
excess refrigerant system pressure (switch open). Via terminals 3 & 4, the second speed coolant fan is switched on 
(switch closed). 
 When -F129- terminals 1 & 2 open, excess refrigerant pressure is initially recognized by A/C control head -E87- and a 
DTC is stored. If the measured outside temperature is between 0  C & 50  C (32  F & 122  F) and -F129- terminals 1 & 
2 remain open for longer than 30 seconds, -E87- switches over from excess pressure to low pressure (Low pressure 
switch function)   page 01
-86
 , Read measuring value block (Display group 01 compressor shut-off conditions). 
Pa
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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
ge 55 of 91 A/C s
ystem, On Board Dia
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)
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01-41
 
VAG1551 scan tool 
display  Possible cause  
Corrective action  
01296  
Sender for Outlet 
Temperature, Center -
G191- 
 
Short circuit to ground /SP 
 
Open circuit/short circuit to 
positive /SP   - Short or open circuit in wiring/connections between -
G191- and -E87- 
- Sensor -G191- malfunctioning- Diagnose and repair short or open 
circuit in wiring using wiring 
diagram 
- -G191- electrical check   page 
01
-115
 
01297  
Sender for Outlet 
Temperature, Floor Outlet 
-G192- 
 
Short circuit to ground /SP 
 
Open circuit/short circuit to 
positive /SP   - Short or open circuit in wiring/connections between -
G192- and  
-E87-. 
- -G192- malfunctioning- Diagnose and repair short or open 
circuit in wiring using wiring 
diagram. 
- -G192- electrical check   page 
01
-115
 
65535  
A/C control head -E87- 
 
Malfunction 
  - Short or open circuit in wiring/connections between 
terminal -15- or -31- to -E87-, contact resistance or 
loose connection 
- -E87- malfunctioning- Diagnose and repair short or open 
circuit in wiring to -E87- using wiring 
diagram 
 
- Replace A/C control head -E87-
Pa
ge 56 of 91 A/C s
ystem, On Board Dia
gnostic 
(OBD
)
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pair&id=AUDI.B5.HA01.01.1