ACC Version I

Application: Mercedes-Benz ’77 – ’81 107; ’76 – ’80 123 and 116 models and Chrysler/Imperial AutoTemp systems

Auto Climate Control (ACC) Servo – Price: $595 plus $75 refundable core charge.
Performance Analysis Company has a permanent solution to a persistent problem for all 1976 to 1981 US model R107, W116 and W123 series Mercedes-Benz automobiles. The ACC system in these models utilizes a control valve housed in a plastic case; the most frequent failure of this device involves cracking of the large upper housing. Coolant leakage through the cracks eventually causes failure of the servo. Undetected loss of coolant can result in a ruined engine. Replacement with an original equipment plastic part is not only expensive, but the plastic replacement unit is also subject to cracking.

PAC instead offers these units with a heat-treated aluminum housing that eliminates the possibility of cracking and subsequent leakage. The PAC units are a direct replacement for the original equipment part in all MBs with the first generation automatic climate control (vertical row of pushbuttons). 

(We buy servo cores – call or email us)


ACC Amplifier – Rebuilt $149 exchange ($75 core charge)
This solid state device is the “brain” of the ACC system. It signals the servo to move in response to changes to inside and outside air temperatures and temperature wheel adjustments. 

(We buy amplifier cores – call or email us)

Auxiliary Water Pump – call regarding availability
Used in auto climate control from 1976, this pump maintains constant coolant flow through the heater. Failure is indicated by decrease in heat during engine idling. Defective pumps can cause failure of push-button panels in 1981+ models.

ACC-DI Climate Control Actuator Diaphragms – Price: $10.50 each 
Designed to repair single and dual diaphragm vacuum actuators used in Mercedes-Benz climate control systems. Our exclusive plastic retainer cup for dual units locks in the diaphragm and protects it from abrasion.