LEMON Manuals: Even more car manuals for everyone
Home >> Mercedes Benz >> 2004 >> G55 >> Repair and Diagnosis >> Heating, Ventilation & A/C (HVAC) >> HVAC Control Systems >> HVAC Testing & Repair -- G-Class (463) >> Testing & Repair >> Remove/install heater unit - AR83.70-P-5302GM

Remove/install heater unit - AR83.70-P-5302GM

MODEL 463.244 /245 /250 with ENGINE 112.945 with CODE (H12) Auxiliary heater 

MODEL 463.247 /248 /254 with ENGINE 113.962 with CODE (H12) Auxiliary heater 

MODEL 463.243 with ENGINE 113.982 with CODE (H12) Auxiliary heater 

MODEL 463.270 /271 with ENGINE 113.993 with CODE (H12) Auxiliary heater 

MODEL 463.309 /332 /333 with ENGINE 628.962 with CODE (H12) Auxiliary heater 

MODEL 463.303 /340 /341 with ENGINE 642.970 with CODE (H12) Auxiliary heater 

MODEL 463.202 /222 /236 with ENGINE 273.969 with CODE (H12) Auxiliary heater 

MODEL 463.306 /336 /346 with ENGINE 642.886 with CODE (H12) Auxiliary heater 

Fig 1: Identifying Heater Unit Components
G07879910Courtesy of MERCEDES-BENZ USA

Illustrated on model 463.333 

REMOVINGINSTALLING Remove/install     
1.1 Remove air filter Engine 628.962 in model 463.309/332/333 AR09.10-P-1050GD
1.2 Remove engine compartment cover with integrated air filter from cylinder head covers vertically upward Engine 112.945 in model 463.244/245/250,
Engine 113.962 in model 463.247/248/254,
Engine 113.982 in model 463.243
 
1.3 Remove air filter housing Engine 113.993 in model 463.270/271 AR09.10-P-1150GX
Engine 273.969 in model 463.202/222/236 AR09.10-P-1150GZG
1.4 Remove left-hand air filter housing Engine 642.970 in model 463.303/340/341
Engine 642.886 in model 463.306/336/346
AR09.10-P-1150GY
2 Remove left hot film mass air flow sensor (B2/6) together with air intake pipe Only on engine 628.962 in model 463.309/332/333 AR07.07-P-1454GD
3 Remove splash guard in wheel well IMPORTANT Remove only the left front splash guard.  
DANGER Risk of injury  to skin and eyes caused by scalding from contact with hot coolant spray. Risk of poisoning  caused by swallowing coolant. Do not open cooling system unless coolant temperature is below 90°C. Open cap slowly and release the pressure. Do not pour coolant into beverage containers.
Wear protective gloves, protective clothing and safety glasses.
AS20.00-Z-0001-01A
4 Release pressure in coolant circuit IMPORTANT To do so open the coolant expansion reservoir cap.
5 Remove STH air filter (1) IMPORTANT On model 463.202/222/236 remove STH air filter (1) from wheel well paneling and clamp of air intake hose from STH or HB [ZUH] heater unit (A6).
IMPORTANT Except on model 463.202/222/236 Remove STH air filter bracket (2) at STH or HB [ZUH] heater unit (A6).
 
6 Detach coolant feed hose (4) and coolant outlet hose (3) MPECIAL TOOL Fig 2
7 Remove coolant feed hose (4) from STH or HB heater unit (A6) IMPORTANT Catch coolant with a suitable vessel.  
NOTES Notes on coolant All engines AH20.00-N-2080-01A
8 Remove coolant outlet hose (3) from coolant recirculation pump IMPORTANT Catch coolant with a suitable vessel.  
NOTES Notes on coolant All engines AH20.00-N-2080-01A
DANGER Risk of explosion  caused by fuel vapors igniting, risk of poisoning  caused by inhaling combustible gases and risk of injury  caused by burns during and after operation of heater unit Do not operate stationary heater, auxiliary heater or engine with heater booster in closed areas or when refueling. Allow heater unit to cool down after operation and wear protective gloves. AS83.70-Z-0002-01A
9 Remove fuel line (5) from STH or HB heater unit (A6) IMPORTANT Collect fuel flowing out in suitable vessel.
10 Detach control line connector (6) and power supply connector (7) IMPORTANT Open retaining clip (8).  
11 Remove exhaust line (9) from STH or HB heater unit (A6)    
12 Remove STH or HB heater unit (A6) IMPORTANT To do so, remove screws/bolts (10) from wheel well.  
13 Remove circulation pump (A6m1)   AR83.70-P-5700GM 
14 Install in the reverse order    
15 Pour in coolant Model 463.244/245/250 with engine 112.945 model 463.247/248/254 with engine 113.962 model 463.243 with engine 113.982 AR20.00-P-1142HA
Model 463.270/271 with engine 113.993
Model 463.202/222/236 with engine 273.969
AR20.00-P-1142GX
Model 463.309/332/333 with engine 628.962
model 463.303/340/341 with engine 642.970
Model 463.306/336/346 with engine 642.886
AP20.00-P-2080G
16 Bleed coolant circuit after completing installation of STH or HB heater unit (A6)   AR83.70-P-5302-01E
17 Check condition of cooling system   AP20.00-P-2050G
18 Perform initial startup of STH or HB heater unit (A6) IMPORTANT If the STH or HB heater unit (A6) switches itself off before reaching its operating temperature and cannot be restarted, there is a fault interlock: ↓  
Connect STAR DIAGNOSIS and read out fault memory IMPORTANT Eliminate fault interlock, see control unit actuation. AD00.00-P-2000-04A
Fig 2: Identifying Clamping Device (000 589 54 37 00)
G07879911Courtesy of MERCEDES-BENZ USA