MERCEDES-BENZ ML350 1997 Complete Repair Manual

Fig. 130: Identifying Fuse And Relay Module, Additional Fan Connector And Plug Connector, Blue
NO REFRIGERATION/HEAT FROM AUTOMATIC AIR CONDITIONER - AF83.40-P-3400A
MODEL 163.### #A as of 289565 up to 458809, 163.### #X as of 754620 up to 777100
Operation no. of operation texts or standard texts and flat rates
If an auxiliary wiring harness (2) has not yet been
installed: ?
3 Install auxiliary wiring harness.SM83.30-P-
0009GH

If an additional wiring harness and a 40 A fuse are
already installed and the auxiliary fan does not
function: ?
4 Perform corresponding diagnosis and repair.

CategoryOp. no.Operation textTimeAcc. no.Code
P831917Replace air conditioning operating unit014 WU--
Damage
codeCauseRemedy
83 491 90The air mixing flap is not actuated by the AAC [KLA]
control and operating unit (N22) because the voltage in
the vehicle electrical system is too low during cold start.
1 Replace AAC [KLA]
control and operating
AR83.40-P-

2001 Mercedes-Benz ML320
1998-2005 HVAC Climate Control - 163 Chassis
me
Saturday, October 02, 2010 3:23:17 PMPage 157 © 2006 Mitchell Repair Information Company, LLC.

Parts ordering notes
HEATER DOES NOT FUNCTION - AF83.40-P-6008A
MODEL 163.154 /174 /175 #A as of 289565 up to 348398 with CODE (494) USA version with CODE (580)
Automatic air conditioning
MODEL 163.113 /154 /174 /175 #A as of 289565 up to 348412, 163.113 /128 #X as of 754620 up to 772006
except CODE (494) USA version with CODE (580) Automatic air conditioning
Modification notes
Operation no. of operation texts or standard texts and flat rates
This fault occurs only on AAC [KLA] control and
operating units (N22) with part number A163 820 25 89,
A163 820 28 89, A163 820 42 89 and A163 820 43 89 unit (N22)6500GH
Part no.DesignationQuantity
163 820 49 89ECE AAC [KLA] control and operating unit1
163 820 50 89USA AAC [KLA] control and operating unit1
12.5.04Information revised in step 11; WE table added; part number revised
CategoryOp. no.Operation text
P023610Perform diagnosis on left air mixing flap actuator motor (M2/6)
Damage
codeCauseRemedy
83 491
90
The automatic air
conditioning control unit
(N22) does not communicate
with the blending air flap
actuator motor (M2/6).
1 Connect STAR DIAGNOSIS and perform short
test.
AD00.00-P-
2000-04A
*WH58.30
-
Z-1048-13A

If fault codes are present: ?
2 Perform diagnosis and repair according to fault
code description.

If NO fault codes are present: ?
Perform following test when engine is cold.
3 Select "Actual values" with STAR DIAGNOSIS
under "Automatic air conditioning".
4 Select "M2/6 (blending air flap actuator motor)".

5 Set temperature control to maximum cooling and
wait 30 seconds Observe the actual value of the
blending air flap actuator motor (M2/6) and switch
over the temperature control switch to maximum
heating.

2001 Mercedes-Benz ML320
1998-2005 HVAC Climate Control - 163 Chassis
me
Saturday, October 02, 2010 3:23:17 PMPage 158 © 2006 Mitchell Repair Information Company, LLC.

Commercially available tools
Parts ordering notes
SELF-DIAGNOSTIC SYSTEM
HEATER, DIAGNOSIS, CONTENTS - AD83.20-P-1000GHZ
MODEL 163
DIAGNOSIS TOOLS, HEATER - AD83.20-P-2000-01GC
Commercially available tools

If the actual value changes, there are not faults
present in the automatic air conditioning control
unit.
6 Perform further diagnosis and repair
correspondingly.

If actual value remains unchanged: ?
7 Remove/install/replace automatic air
conditioning control unit.AR83.40-P-
6500GH
8 Install components removed in opposite order.
9 Select "Control module adaptation" with STAR
DIAGNOSIS under "Automatic air conditioning".
10 Select "Read coding and change if necessary".

11 Adjust "National version" according to
customer's request
Settings for blower and temperature: ?
"Rest of the world". = Minimum
"USA" = Standard
"----" = Maximum

12 Adjust "LED dimming" according to "SERIES"
13 Adjust further coding according to vehicle
specifications.
NumberDesignation
WH58.30-Z-1048-13ASTAR DIAGNOSIS diagnosis system, Compact Passenger Car6511 1801 00
Part no.DesignationQuantity
163 820 49 89Switch unit/automatic air conditioning control unit, ECE1
163 820 50 89Switch unit/automatic air conditioning control unit, USA1
K 1.8 [] 11Heater, diagnosis, basic knowledge AD83.20-P-2000GH
K 1.8 [] 12Heater, diagnosis, function check AD83.20-P-3000GH
NumberDesignation

2001 Mercedes-Benz ML320
1998-2005 HVAC Climate Control - 163 Chassis
me
Saturday, October 02, 2010 3:23:17 PMPage 159 © 2006 Mitchell Repair Information Company, LLC.

HEATER, DIAGNOSIS, BASIC KNOWLEDGE - AD83.20-P-2000GH
MODEL 163
HEATER CAPACITY, FUNCTION CHECK, HEATER - AD83.20-P-3000-01GH
Test sequence
Heater switch (2) on "red" stop
Blower switch (1) on stage 4
Air distribution switch (3) in 12 o'clock position
Recirculated air button ( ) not pressed (LED does not come on)
Test period > 5 minutes
Engine speed 2000 rpm
Engine coolant temperature > 80°C
 Read out temperature measuring instrument (4)
Temperature display > 55°C

If the measured values stated above are not achieved, the following components and functions should be
checked:
Engine coolant temperature
Furring in cooling system and heat exchanger
Blend air flap function
Coolant circulation pump (M13)
WH58.30-Z-1002-08ADigital temperature measuring instrument (measuring range -20° to +70°)
WH58.30-Z-1004-08AAir temperature probe
Electric wiring diagrams, location of ground points and connectors PE83.00-P-1100E
Connection and use of test equipment AD00.00-P-1000AZ
Diagnosis tools, heater AD83.20-P-2000-01GC

2001 Mercedes-Benz ML320
1998-2005 HVAC Climate Control - 163 Chassis
me
Saturday, October 02, 2010 3:23:17 PMPage 160 © 2006 Mitchell Repair Information Company, LLC.

Fig. 131: Identifying Heater Capacity, Function Check, Heater
HEATER, DIAGNOSIS, FUNCTION CHECK - AD83.20-P-3000GH
MODEL 163
Heater, diagnosis, basic knowledge AD83.20-P-2000GH
Check fuses F1/6, F1/41, F1/43

Allow engine to idle at operating
temperature (approx. 80°C engine coolant
temperature) throughout the entire test
period

Outside temperature > 15°C
Open center and side air outlets manually
Recirculated air button ( ) is not
pressed (LED does not come on)
Blower switch on stage 4
Function check
Test
step/Scope of
test
Operation/Requirement Specified value Possible cause/ Remedy
1
No heat Heater switch on "blue" stopAir outlets,
unheated airWire cable for
actuating blend air
flap

2001 Mercedes-Benz ML320
1998-2005 HVAC Climate Control - 163 Chassis
me
Saturday, October 02, 2010 3:23:17 PMPage 161 © 2006 Mitchell Repair Information Company, LLC.

AIR CONDITIONING (TEMPMATIC) DIAGNOSIS CONTENTS - AD83.30-P-1000GHZ
MODEL 163 with CODE (580) Air conditioning or for USA, Tempmatic
AIR CONDITIONING (TEMPMATIC) PRECONDITIONS FOR OPERATIONAL CHECK - AD83.30-P-2000-01GH
up to 30.11.99
Heater push-button
unit
2
Full heat Heater switch on "red" stopAir outlets, heated
air
Wire cable for
actuating air blend
flap
Heater push-button
unit
3
Recirculated
air mode Heater switch in any position Recirculated
air button ( ) is pressed (LED comes
on)Air flow from
center outlet
increases
noticeably
Cables
Recirculated air
button
Actuator motor for
recirculated air flap
element (M39)
Heater push-button
unit
4
Heat output Connect temperature measuring instrument
Heater switch on "red" stop
Air outlet
temperature at
defroster outlet >
55°C
Engine coolant
temperature
Hot water coolant
circulation pump
Furring in cooling
system and heat
exchanger
Test sequenceAD83.20-P-3000-01GH
K 2.6 [] 11Air conditioning (Tempmatic) (Tempmatic A/C) diagnosis, previous
knowledge AD83.30-P-
2000GH
K 2.6 [] 12Air conditioning (Tempmatic) (Tempmatic A/C) diagnosis, function
check AD83.30-P-
3000GH
K 2.6 [] 13Air conditioning (Tempmatic) (Tempmatic A/C) diagnosis, function
check actual values AD83.30-P-
3001GH
K 2.6 []
14AAir conditioning (Tempmatic) (Tempmatic A/C) diagnosis, fault memory AD83.30-P-
4000GH
K 2.6 [] 21Air conditioning (Tempmatic) (Tempmatic A/C), testing electrical
system AD83.30-P-
6000GH

2001 Mercedes-Benz ML320
1998-2005 HVAC Climate Control - 163 Chassis
me
Saturday, October 02, 2010 3:23:17 PMPage 162 © 2006 Mitchell Repair Information Company, LLC.

Fig. 132: Locating In-Car Temperature Sensor With Aspirator Nozzle
1. Check condition of fuses F16, F41, F43, F44.
2. Check aspirator nozzle for in-car temperature sensor as follows: With ignition switched on, place a piece
of paper (arrow) of 1cm surface area on grill in front of in-car temperature sensor with aspirator nozzle
(B10/4). With sufficient ventil ation (aspirator nozzle to blow er), paper remains on grill.
3. Allow engine to idle at operating temperature (engine coolant temperature approx. 80°C) during the
complete duration of the test.
4. Outside temperature > 15°C.
5. Open center and side air outlets manually.
6. Recirculated air switch not pressed.
7. Set blower switch to stage 4.
AIR CONDITIONING (TEMPMATIC ) PRECONDITIONS FOR OPERATIONAL CHECK - AD83.30-P-2000-01GK
as of 1.12.99

2001 Mercedes-Benz ML320
1998-2005 HVAC Climate Control - 163 Chassis
me
Saturday, October 02, 2010 3:23:17 PMPage 163 © 2006 Mitchell Repair Information Company, LLC.

Fig. 133: Locating In-Car Temperature Sensor With Aspirator Blower
1. Check status of fuses F16, F41, F43, F44.
2. Check aspirator blower for in-car temperature sensor: With ignition switched on, place a piece of paper
(arrow) of 1cm surface area on grill in front of in-car temperature sensor (B10/4) with aspirator blower.
With sufficient ventilation (a spirator blower to blower), paper remains on grill.
3. Allow engine to idle for entire duration of test at operating temperature (approx. 80°C coolant
temperature).
4. Outside temperature > 15°C
5. Open center and side nozzles manually.
6. Recirculating air sw itch not pressed.
7. Blower switch on step 1.
Observe run-on time.
AIR CONDITIONING (T EMPMATIC) VERSION CO DING - AD83.30-P-2000-02GH
Variant coding is carried out by the HHT and is menu -assisted. Communication is possible as soon as the
ignition key is inserted in the ignition lock (the igniti on lock position is not important). Variant coding (position
1) is reached from the main menu via control module adaptations (position 5). The following two options are
available in variant coding:
1. Read out coding and transfer to new control module.
2. Readout/change coding.
Position 2 must be selected in order to read out th e air conditioning coding. The air conditioning variant coding
is found under position 07 in the following listing.

2001 Mercedes-Benz ML320
1998-2005 HVAC Climate Control - 163 Chassis
me
Saturday, October 02, 2010 3:23:17 PMPage 164 © 2006 Mitchell Repair Information Company, LLC.

Here a selection can be made between:
1. fitted and
2. not fitted
AIR CONDITIONING (TEMPMATIC) NOTES ON FAULT MEMORY - AD83.30-P-2000-03GH
A particular numerical code is assigned to each fault (short-circuit, open-circuit, etc.) which distinguishes
between current faults and faults which occur temporarily.
When determining faults, the push-button control unit (N19) cannot always distinguish between short-circuit
and disconnected cables.
If no fault code is displayed, but there is a complaint, a tolerance deviation of components can exist. Since such
a deviation is not recorded by the fault memory, the appropriate test steps are to be checked with the socket box
and Multimeter.
AIR CONDITIONING (TEMPMATIC) DIAGNOSIS TOOLS - AD83.30-P-2000-04GH
Commercially available tools
AIR CONDITIONING (TEMPMATIC) TEST OF ELECTRICAL SYSTEM TOOLS - AD83.30-P-2000-06GH
Fig. 134: Identifying 35-Pin Socket Box (124 589 00 21 00)
Coding optionsSelection
Air conditioningfitted/not fitted
NumberDesignation
WH58.30-Z-1036-13AHandheld tester (HHT)651 100 01 99
WH58.30-Z-1037-13ATest cable (multiplexer)651 100 40 99

2001 Mercedes-Benz ML320
1998-2005 HVAC Climate Control - 163 Chassis
me
Saturday, October 02, 2010 3:23:17 PMPage 165 © 2006 Mitchell Repair Information Company, LLC.

Fig. 135: Identifying Fu sed Cable (124 589 37 63 00)
Fig. 136: Identifying Test Cable 14
-Pin (163 589 01 63 00)
Commercially available tools
AIR CONDITIONING (TEMPMAT IC) SOCKET BOX CONNECTION DIAGRAM - AD83.30-P-2000-07GH
NumberDesignation
WH58.30-Z-1001-09AMultimeter

2001 Mercedes-Benz ML320
1998-2005 HVAC Climate Control - 163 Chassis
me
Saturday, October 02, 2010 3:23:17 PMPage 166 © 2006 Mitchell Repair Information Company, LLC.