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.
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Page 59 of 91

01-43
Notes:
During Output DTM on vehicles with Control Head (E87) Part Number 8D0 820 043 D, A/C Compressor Clutch (N25) DTC
"01270, mechanical malfunction SP" may be stored even though no malfunction is present. Corrective action: When
output DTM is complete, check DTC memory. If above DTC is present, erase DTC memory.
When starting Output DTM, temperature and air distribution flap flap motors move to pre-determined positions in
preparation for individual tests: Temperature Regulator Flap Motor V68: moves to "heat" position. Central Air Flap Motor -
V70- moves to "floor & defroster outlet" position. Footwell Defroster Flap Motor V85 moves to "defrost" position.
Output DTM can be repeated several times, if necessary.
During Output DTM, vehicle must not be moved and engine speed must be less than 3000 rpm.
During Output DTM, A/C system control is switched off and all segments in both A/C control head displays are actuated.
Interior temperature sensor fan -V42- is activated via an A/C control head:
with one display after activation of the coolant fan.
with two displays after activation of air flow flap motor.
Outside air temperature display -G106- is activated via an A/C control head
with one display after activation of air flow flap motor.
with two displays after activation of idle regulation.
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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 63 of 91
01-45
Notes:
If a DTM component fails to respond as
specified, perform all corrective actions, checks
and tests recommended in output DTM table
page 01
-46
.
A/C system component locations: engine
compartment page 87
-96
(note specific
model year information).
A/C system component locations: passenger
compartment page 87
-106
(note specific
model year information).
Output DTM can be ended by pressing the -C-
button.
After ending output DTM, check DTC memory
page 01
-18
.
If the readout "function unknown or cannot be
carried out at the moment" appears in the
display at the start of output DTM, e.g. when
engine not running, press button and once
again select "function 03 Output Diagnosis Test
Mode (DTM)" (DTM component "A/C Clutch
N25" is no longer actuated for this test).
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Page 65 of 91

01-46
Output Diagnostic Test Mode (DTM) table
VAG1551 scan tool display
Specified function
Corrective action
A/C Clutch N25
Notes: - N25 clicks every 2-seconds
- Output of A/C control head -E87- is switched from 0 V to
12 V every 2-seconds2) - Test voltage supply for -
N25- (via A/C Clutch
Relay J44) using wiring
diagram
- Repair or replace -N25-
page 87
-90
- Test circuit and
connectors between A/C
control head -E87-, J44
and -N25- using wiring
diagram
- Replace -E87-
"A/C compressor on" output to
Engine Control Module (ECM)
and -E87- terminal -C12- is
also actuated at the same
time1)
Output of -E87- switched from 0 V to 12 V every 2
seconds can be confirmed by switching compressor on
and off using the "ECON" button while reading the
measured value block of engine control module
Repair Manual, Fuel Injection and Ignition System,
Repair Group 01)
1)Test this "A/C compressor on" signal only if complaints exist. ECM uses signal to compensate for engine load when
compressor engages Repair Manual, "Fuel Injection & Ignition," Repair Group 24 . ECM is capable of switching off the A/C compressor from this signal. Confirm via function 08, Read measuring value block,
page Page 01
-63
, display group 01 and Fuel Injection and Ignition System Repair Manual, Repair group 01: Read
measured value block of ECM with engine running and at same time switch compressor on and off.
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Page 76 of 91
01-54
Notes:
For m.y. 1996, because A/C engine coolant
temperature sensor G110 is not installed on
USA/CDN models, during basic setting, DTC
"00799 engine coolant temperature sensor
G110" is stored and must be erased.
For m.y. 1997 A/C engine coolant temperature
(ECT) sensor -G110- is deleted, and will no
longer load a DTC when checking DTC memory
after ending basic setting.
- Check DTC memory page 01
-18
.
- Erase DTC memory (function 05) and end
output (function 06) page 01
-55
.
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Page 81 of 91
01-57
Code Control Module (function 07)
A/C control head -E87- coding, vehicles 1996
Notes:
A/C control head coding 1997 page 01
-
59
.
A/C control head coding 1998 page 01
-
61
.
A/C control head -E87- coding shows market
application, compressor type and engine type.
Notes:
Zexel A/C compressors are installed from start
of production. During m.y. 1996, Nippondenso
type compressors are installed as a running
change. These compressors are not equipped
with A/C speed sensor G111.
Each time A/C control head -E87- is coded,
basic setting must be performed page 01
-
52
.
If a the display of a newly installed A/C control
head -E87- flashes after switching ignition on
(for approximately 2 minutes), code the control
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Page 83 of 91
01-58
Rapid data transfer
HELP
Select function XX
Indicated on display
- Press buttons -0- and -7-.
Rapid data transfer
Q
07 - Code Control Module
Indicated on display
- Press -Q- button to confirm input.
Code Control ModuleEnter code number XXXXX
Indicated on display
Coding m.y. 1996:
Note:
Coding example, m.y. 1996: 0 0 1 6 2
0 = open
0 = open
1 = compressor w/o Compressor Speed Sensor -G111-
(0 = compressor with -G111-) -
Press button.Code
Market
Compressor
Engine
00062
USA/CDN
Zexel
6-cylinder gasoline
00162
USA/CDN
Nippondenso
6-cylinder gasoline
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