DTC 85

DTC 85 Chart:

CIRCUIT DESCRIPTION
The Powertrain Control Module (PCM) continuously learns base idle position. This base idle position is the relationship of engine RPM to throttle position. The PCM is limited to a fixed amount of learned throttle angle that it can apply. When this limit is reached, DTC 85 will set. The cause of this increase in learned throttle angle is usually deposits in the throttle body.

DTC 85 WILL SET WHEN
- A/C "OFF," idle learned throttle angle 3.9 degrees or greater.
OR
- A/C "ON," idle learned throttle angle 3.9 degrees or greater.

ACTION TAKEN (PCM WILL DEFAULT TO)
With a current DTC 85 set, the PCM will illuminate the Malfunction Indicator Lamp (MIL) (Service Engine Soon).

DTC WILL CLEAR WHEN
The fault no longer exists.

DTC CHART TEST DESCRIPTION
Number(s) below refer to circled number(s) on the diagnostic chart.

1. Checking for other throttle position DTC(s) being set that can cause other throttle body problems.
2. Checking if throttle body deposits are causing the increase in the learned throttle angle Also, a loose fitting air cleaner or air intake duct may allow debris to enter the throttle body
3. Checking if ISC motor can retract far enough to close throttle position switch.
4. Checking for proper operation of the ISC motor.

DIAGNOSTIC AIDS
DTC 85 may set due to an engine overheated condition in which the PCM will only allow the engine to run on four cylinders, causing a high idle throttle angle. If this occurs, clear DTC 85, reset idle learn using Tech 1 and perform TP sensor/idle learn.