Where is the fuel pump relay on a Mercedes Benz SL?
Various components of the CIS-E injection system are checked by a microprocessor in the control unit. The failure codes are transmitted by the lambda measuring circuit of the diagnostic socket and are displayed on the Bosch On-Off Ratio Tester (KDJE-P600). The fuel pump relay on 560 SL models is located behind the glove compartment.
Where is the voltage protection relay on a Mercedes Benz?
Voltage protection relay is used to protect the ECU from excessive voltage. There is a 10-amp fuse installed on top of the VPR, which is located on relay board at right side of engine compartment. When ignition is switched on, terminal No. 15 receives battery voltage.
Where is the coolant temperature sensor located on a Mercedes 190?
The coolant temperature sensor is located in the left cylinder head. The sensor has a 2-pin connector, one for Electronic Ignition System (EZL) and one for the CIS-E injection system. On 190 series, the ECU is located on right side of engine on the firewall.
What are the electronic controls in a Mercedes Benz?
Electronic controls consist of airflow sensor position indicator (potentiometer), electro-hydraulic actuator, thermo time switch, coolant temperature sensor, Electronic Control Unit (ECU), transistorized ignition system, throttle valve microswitch, altitude sensor, lambda control and oxygen sensor.
Where is the OVP relay located on a Mercedes Benz?
On W126 chassis it is located between the 2 firewalls underneath the hood. On W107 chassis it’s located behind the right kick panel. Check the 10 amp fuse on top of it first. If it is blown, replace it. If it is good, check the socket that that the fuse sits in for corrosion. Clean and/or replace as necessary.
What does the Mercedes over voltage protection relay do?
The Mercedes over voltage protection relay provides voltage to the ABS and Mercedes engine control units. In the case of hard start, when you cut off the voltage supply to the engine control unit, you loose all of your cold idle circuits.
What happens if the overload protection relay is blown?
No voltage equals all kinds of drivability problems. Tech Tip: When checking voltage at the pins of the overload protection relay pin 30 is hot with the key on and pins 87 are the output voltage to the control units. If the relay is blown there will not be voltage present at pins 87.
What does the relay have to do with the way my car runs?
The relays were also known to have weak solder joints from factory and go prematurely bad, but chances are the relay was doing its job protecting your car’s control units, and give thanks that it did. The components it was protecting are expensive. What does the relay have to do with the way my car runs?