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	 1991 Mercedes-Benz 300SEL 3.0L heat 
		
		Customer complaint that he only has heat coming out of defrost vents,there is no heat from any other vents,I did manually pull vacuum on port 4 on the switch over valve and heat did start coming out center vents.I need to to know how to test the push button sw... 
                        
                            FIX posted 12/21/2017
                             
                 
                            
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| VIN | WDBCA25D0M | 
| Engine | 3.0 L / 6 cyl / GAS | 
| Trans | 4-speed Automatic | 
| Delivery | Fuel Injection | 
| Affected | Heat | 
| Conditions | Only Out of Defrost | 
Message Closed
            
            
 Vehicle Data
                1991 Mercedes-Benz 300SEL
| VIN | WDBCA25D0M | 
| Engine | 3.0 L / 6 cyl / GAS | 
| Trans | 4-speed Automatic | 
| Delivery | Fuel Injection | 
| Affected | Heat | 
| Conditions | Only Out of Defrost | 
                            
9 Replies Received
          9 Replies Received
          
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