Federal Models

Fig. 59 CIS-E I/O Diagram:

The CIS-E control unit evaluates information provided by various sensors concerning the engine operating conditions,

Fig. 9 CIS-E Control Unit:

and from the information generates a control signal for the electro-hydraulic actuator. The electro-hydraulic actuator regulates pressure in the lower chambers of the CIS-E fuel distributor which provides for the optimal fuel quantity required by the engine. Furthermore, the CIS-E control unit provides an output signal for operation of the fuel pump relay, idle control valve, diagnostic socket (air/fuel mixture information, and fault diagnosis), and the "CHECK ENGINE" light operation.

Fig. 72 Bosch On/Off Ratio Tester:

Malfunctions resulting from open or short circuits or failure of the oxygen sensor will be indicated by the "Check Engine" light at the instrument cluster. Because the CIS-E control unit does not have memory capabilities, intermittent failures may cause the "CHECK ENGINE" light to flicker or go out when the fault is not present. Fault diagnosis is accomplished by the use of the Bosch on/off ratio tester (KDJE-P 600 Lambda tester) via the diagnostic socket.