Removing and installing rear heater supply unit - AR83.50-P-8940D

MODEL 140 with CODE (582) Air conditioning in rear 

Fig 1: Identifying Heater Supply Unit

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

	Removal
1	Relieve pressure in cooling system	For this purpose turn radiator cap to catch "1" and then close again
2	Remove inner fender in front fender		ra88001290130x
3	Disconnect electrical connectors from heater supply unit (A31)
4	Loosen hose clamps on heater supply unit (A31)
5	Disconnect hoses from heater supply unit (A31) and plug openings (parts kit)
6	Press out rubber mount (arrow) and remove heater supply unit (A31)
	Installation
7	Install heater supply unit (A31) on rubber mounts (arrows)	Ensure that unit is seated properly
8	Connect hoses to heater supply unit (A31)
9	Tighten hose clamps on heater supply unit (A31)
10	Connect electrical connectors to heater supply unit (A31)
11	Correct coolant level
12	Bleed heater by setting both temperature dials for rear air conditioning to catch position in "red" field and allowing engine to run at alternating speed
13	Check heater supply unit (A31) for proper function	Power consumption < 1.2 A
14	Erase DTC memory in A/C (autom.)/CNS/ICS control module
15	Install inner fender in front fender		ra88001290130x