Locks - Central Locking System Modifications
84mercedes03TO: OUR MERCEDES-BENZ PASSENGER CAR DEALERS
DATE: March, 1984 REF. NO. 80/14
SUBJECT: MODIFICATIONS TO CENTRAL LOCKING SYSTEM MODELS 123 AND 126
A. CONTROL VALVE MODEL 123, EXCEPT 123.150/153
B. DOOR ACTUATOR MODEL 123
C. RELOCATION OF CHECK VALVE MODEL 123 D.. SUPPLY PUMP AND LOCK ACTUATORS MODEL 126
FIGURE 1 - PREVIOUS VERSION:
FIGURE 2 - MODIFIED VERSION:
A. Control Valve - Model 123, Except 123.150/153
Since July 1983, a modified control valve (Figure 2) with an improved seal for cold weather operation was phased into production. Unlike the previous version, the new valve does not require adjustment during installation. The modified control valve can only be installed in previous vehicles in conjunction with the following parts: Link (2), pull rod (3), screws B 4.2 x 25 mm (4) with washers (Figure 2).
Parts Information
Quantity Part Name Part Number
1 Control valve (modified) 000 800 10 73
1 Pull rod 123 723 07 69
1 Link 123 805 01 32
2 Screw 007981 004250
2 Washer 000125 004313
FIGURE 3 VACUUM ACTUATOR (VDO):
FIGURE 4 VACUUM ACTUATOR (ALFMEIER):
B. Door Actuators - Model 123
Since March 1983, vacuum actuators (Figure 4), manufactured by Alfmeier, were installed in doors with a modified actuating rod connector. The vacuum actuator made by VDO (Figure 3) remains unchanged. Actuators from both manufacturers are interchangeable.
FIGURE 5:
Replacement Procedure
1. Install the modified actuator with the previously removed screws.
2. Push down door lock button.
3. Completely pull out slotted actuating rod connector (a, Figure 5) while pushing locking sleeve (b) down at the same time.
4. Insert grooved portion of actuating rod (c) into rod connector and push locking sleeve up against stop, while holding the actuating rod in place.
FIGURE 6 - PREVIOUS LOCATION OF CHECK VALVE:
FIGURE 7 - RELOCATED CHECK VALVE:
C. Relocation of Check Valve - Model 123
As of June 1983, the central locking system check valve has been relocated from behind the instrument cluster (arrow, Figure 6) into the driver's door (arrow, Figure 7).
Production Phase-In
Model As of Chassis End Number
123.123 409814
123.133 033624
123.153 003790
123.193 017218
D. Supply Pump and Lock Actuators - Model 126
Since July 1983, the model 201 supply Pump (rotation changes for vacuum/pressure) was installed in model 126.
New actuators (20 mm shorter than in model 201) for the fuel filler door and trunk lid were also phased into production.
A locking sleeve is now used to connect the actuator rod, instead of a clip.
Production Phase-In
Model As of Chassis End Number
126.032/033 049170
126.037 037297
126.120 051493
126.043 008087
126.044 007459
NOTE: The new supply pump and new foam housing, as well as the control actuator (drivers door) and door actuators can also be installed in earlier production vehicles. The previous version actuators in stock can be used up.
FIGURE 8:
Installation of Modified Actuators
1. Remove actuator.
2. Prior to installing the new control actuator (2, Figure 8) slide the locking sleeve (arrow) down while applying a counterhold from the bottom with a 4 mm pin (a).
3. Prior to installing a door, fuel filler flap, or trunk lid actuator, thumb-seal the vacuum connection and slide the locking sleeve down to the stop.
4. Fasten actuator with previously removed screws.
FIGURE 9:
5. Insert actuator rod without preload into rod connection, while pushing slip joint (arrow, Figure 9) up to its stop.
Parts Information
Part Name Part Number
Supply pump 000 800 03 48
Foam housing 126 805 03 90
Control actuator 002 820 55 10
Door actuator 000 800 71 75
Fuel filler flap and
trunk lid actuator 000 800 72 75