California
EGR Control Solenoid Circuit:
Engine Control Module Connector--For Pin Applications See Components:
COMPONENT TEST
NOTE: Mark vacuum hoses prior to disconnecting--so they can be connected properly after test.
Fig. 37 Connecting A Vacuum Pump To The EGR Control Solenoid Valve:
1. Disconnect the green striped and yellow striped vacuum hoses from the EGR solenoid valve.
2. Disconnect the electrical connector.
EGR Voltage Test:
3. Connect a hand vacuum pump to the fitting the green striped hose was connected to.
EGR Resistance Test:
4. Apply vacuum to the solenoid with the pump and note the results when battery Voltage is applied and not applied to the electrical connectors--as shown.
a. Vacuum should hold when Voltage is applied.
b. Vacuum should NOT hold when NO Voltage is applied.
5. Using an Ohm meter check the resistance across the solenoid terminals.
Resistance:
36 - 44 Ohms @ 68° F.
HARNESS TEST
1. Disconnect the EGR solenoid connector and turn the key to the ON position.
2. Using a Voltmeter, measure the supply Voltage--from the MFI relay--at harness connector terminal 1
Voltage: System Voltage.
3. Turn the key OFF and disconnect the negative battery cable.
4. Using an Ohmmeter, check for continuity between the ECU harness connector terminal 6 and and solenoid connector 2.
Continuity: Should exist.
5. Disconnect the ECU connector. Using an Ohmmeter, check for continuity between the ECU harness connector terminal 6 and ground.
Continuity: Should not exist.
6. Using an Ohmmeter, check for continuity between the solenoid connector terminal 2 and ground.
Continuity: Should not exist.
If any of the previous tests produce unsatisfactory results, the harness will need to be repaired or replaced. Once repairs have been completed, clear the trouble codes and road test the vehicle to confirm that the repair has corrected the problem and the code doesn't return.
If the trouble code returns, it is possible that there is an intermittent failure of the component or the ECU. Check for looseness at all harness junctions and test for an intermittent failure.