P0510

Diagnostic Chart:

Wiring Diagram:

Circuit Description

The Idle Speed Control (ISC) motor sends a Closed Throttle Position (CTP) switch signal to the Powertrain Control Module (PCM). The PCM applies 5 volts to the CTP switch. The CTP switch is closed with the engine idling (low voltage signal at the PCM) and open with the engine off idle (high voltage signal at the PCM). When the PCM detects a low voltage signal the throttle valve is closed, and when the PCM detects a high voltage signal the throttle valve is open.


Conditions for Setting the DTC

^ Off to on time: vehicle speed change from 0 to 32 km/h (0 to 20mph) for 16 times.

^ On to off time: vehicle speed change from 0 to 32 km/h (0 to 20mph) for 16 times.

Action Taken When the DTC Sets

^ The Malfunction Indicator Lamp (MIL) will illuminate after two consecutive ignition cycles in which the diagnostic runs with the fault active.

^ The PCM will record operating conditions at the time the diagnostic fails. This information will be stored in the Freeze Frame buffer.


Conditions for Clearing the MIL/DTC

^ The MIL will turn OFF after three consecutively passing cycles without a fault present.

^ A History DTC will clear after 40 consecutive warm-up cycles without a fault.

^ DTCs can be cleared by using a scan tool or by disconnecting the PCM battery feed.

Diagnostic Aids

Check for any of the following conditions:

^ When a DTC P0107, P0122, and P0510 are set, check for an open in the reference circuit (LT. GRN wire) An incorrectly adjusted Throttle Position (TP) sensor could cause a DTC P0510 to set. Refer to TP Sensor Replacement/Adjustment. Adjustments

^ A poor connection at the PCM. Inspect the harness connectors for backed out terminal, improper mating, broken locks, improperly formed or damaged terminals, and a poor terminal to wire connection.

^ A damaged wiring harness. Inspect the wiring harness for damage and repair as necessary.

If a DTC P0510 cannot be duplicated, the information included in the Freeze Frame data can be useful in determining vehicle operating conditions when the DTC was first set.

It any wiring repairs need to be made, Refer to Repair Procedures in Electrical Diagrams.


Test Description

The numbers below refer to the step numbers in the Diagnostic Table.

1. The Powertrain OBD System Check prompts the technician to complete some basic checks and store the freeze frame data on the scan tool if applicable. This creates an electronic copy of the data taken when the fault occurred. The information is then stored in the scan tool for later reference.

2. This test will determine whether the fault is present now. The scan tool should read IDLE when the throttle is closed and should read NOT IDLE when it is opened.

3. Review Freeze Frame data to determine when the DTC set. Always record this information.