Pinpoint Test E

Enter this pinpoint test only when service Codes 27 and/or 28 are in the KEY ON, ENGINE RUNNING SELF-TEST. This pinpoint test is intended to diagnose speed control servo and vacuum hose connections (servo-to-manifold and servo-to-dump valve).

1. Service Code 27 appears. Repeat KEY ON, ENGINE RUNNING SELF-TEST. Ensure speed control "ON" button is pressed before pressing "STAR" push button. If Code 27 is still present, go to next step. If not, the servo leaks-down-test passed. Service any other service code that may appear.
2. If servo vacuum supply hose is not tightly connected to servo and vacuum manifold, and is not free of cuts or cracks, service vacuum hoses. Repeat QUICK TEST  . If okay, replace the servo and repeat the QUICK TEST  . If dump valve hose is not tightly connected to servo and dump valve, and is not free of cuts or cracks, service the vacuum hoses. Repeat QUICK TEST  . If okay, replace the servo and repeat the QUICK TEST  .
3. Service Code 28 appears. Repeat KEY ON, ENGINE RUNNING SELF-TEST. Ensure speed control "ON" button is pressed before pressing "STAR" push button. If Code 28 is still present, replace servo and repeat QUICK TEST  . If not, servo leaks-up-test passed. Service any other service codes that appear as necessary.