Air Recirculating Valve and Transducer

FIG. 73, Vacuum Transducer mbar / mA Values:

1. Air recirculating valve.
Connect a vacuum tester to the air recirculating valve and apply about 400 mbar of vacuum. If the vacuum drop exceeds 50 mbar / min., replace the valve.

2. Air recirculating valve vacuum transducer
a. Connect a vacuum gauge, with a 'T' fitting, between the air recirculating valve, and vacuum transducer (Y31).
b. Connect a multimeter to the electrical connections on the transducer.
c. Test values should be:
Idle 60 mbar (max.) / 0 mA
1300 rpm approx. 500 mbar / approx. 900 mA (see Fig. 73)
d. If current at the vacuum transducer is too high, check to see that the vent line to the passenger compartment, and its filter are open.
e. If the current is too low;
1. Check if the vacuum supply line is blocked.
2. Check if the vacuum line between vacuum transducer and air recirculating valve is interrupted.
3. Check the vacuum pump.
f. If vacuum lines are OK, replace the air recirculating valve vacuum transducer.

3. With the engine off, disconnect the 2 pin plug on the vacuum transducer (Y31), and check to see that there is battery voltage at the plug.
a. If there is no voltage, repair wiring.
b. If voltage is present, replace EDS control unit.