Manual Trans

Throttle Switch (M/T Only):

Code 21 Wiring Diagram:

CIRCUIT DESCRIPTION:

On manual transaxle cars the ECM supplies 4-5 volts to a throttle switch on the throttle body. When engine is idling the ECM sees a low voltage signal at Terminal "A3." At slight throttle the ECM will see a high voltage signal at Terminal "A3." At wide open throttle the signal voltage on Terminal "A15" is low. Code 21 will set if the ECM sees the signal voltage at Terminals "A3" and "A15" and remain above 4-9 volts, at the same time, for more than 0.3 seconds (indicating idle and WOT simultaneously).

TEST DESCRIPTION: Numbers below refer to circled numbers on the diagnostic chart.

1. The ECM supplies 5.0 volts to the throttle switch. Poor connection or a ground circuit will indicate a low signal.

2. This will check circuit for short to ground or misadjusted throttle switch.

DIAGNOSTIC AIDS:

An intermittent may be caused by a poor connection, rubbed through wire insulation, or a wire broken inside the insulation. Inspect ECM harness connectors for backed out terminals, improper mating, broken locks, improperly formed or damaged terminals, poor terminal to wire connection and damaged harness. For additional information, Testing and Inspection