Chart 6EC-1 EGR System Check

Chart 6E-C-1:

EGR Valve Circuit:

CIRCUIT DESCRIPTION
This procedure tests the Exhaust Gas Recirculation (EGR) system's ability to functionally regulate the amount of exhaust gas fed to the engine.

NOTES ON FAULT TREE
1. Checking if by using Powertrain Control Module (PCM) overrides the EGR valve can be shut off (less than 103 counts).

2. Checking if by using PCM overrides the EGR valve can return to full on (greater then 200 counts).

3. Checking CKT 741 and fuse "D1" for an open.

4. Checking if EGR valve is open circuited.

5. Checking if CKT 435 is open.

6. Checking if PCM is open internally or if CKT 435 is shorted to voltage.

7. EGR valve control circuits are OK. Checking to see if the EGR valve can respond correctly to the signal being sent to it from the PCM.