Movement of the throttle plate is achieved with the use of a motor and two springs. One spring aids travel from wide-open throttle position to reduced power mode position, and the other spring aids in travel from reduced power mode position to completely sealed. A spring check is performed at the beginning of every ignition. The throttle butterfly starts at reduced power mode position, and is allowed 0.5 seconds to open as far as possible. Another 0.5 seconds are allowed for the throttle plate to return to the original reduced power mode position. If the return position deviates a certain amount from the original start position, this code will set.
DTC PARAMETERS
DTC P1523 will set if the return position deviates from start position greater than 3% when:
| • | Condition exists for longer than 0.56 seconds |
| • | Vehicle speed not present |
| • | Engine speed less than 250 rpm |
| • | ECT is between 5°C-100°C (41°F-212°F) |
| • | IAT greater than 5°C (41°F) |
P1523 is a (type D) DTC
DIAGNOSTIC AIDS
Carbon deposits may restrict proper movement of the throttle plate in the short time allotted for this test.
Check for TP sensor DTCs. If present, diagnose those first.
Spring retention capabilities may degrade with time. Throttle assembly may need to be replaced.
If both P1510 and P1523 are set, circuit 485 may be shorted to voltage.
