Service manual

EDI DIAGNOSIS
SERVICE MANUAL NUMBER 22
90-860074--1 FEBRUARY 2002 Page 5E-21
TEST DESCRIPTION:
Verify continuity between the following pins:
ECM 68 PIN CONNECTOR
4 TERMINAL CONNECTOR AT ECT
40 4
41 3
55 1
DIAGNOSTIC HELP:
Verify the following:
• Open or short in the CKT Pin 40, CKT Pin 41 or CKT Pin 55 will cause low amount of
smoke.
• Assembly loose on manifold or a damaged O-ring seal, causing improper signal. Will
cause high amount of smoke.
• Bent terminal or pin at the MAP connection or ECM.
• Defective MAP or ECM.
MAP failure influences engine performance as follows:
• FUEL QUANTITY ACTUATION: Maximum engine rpm is 70% of the normal
operating range (45% of fuel quantity reduction).
NOTE: Failure of the MAP and IAT sensor at the same time will limit engine performance
to 60% maximum of the normal operating range (50% fuel quantity reduction).
IMPORTANT: Replace the O-ring seal whenever removing the MAP/IAT sensor.
Torque the sensor to specification when replacing.