Power Take-Off (PTO) Indicator Inoperative

Power Take-Off (PTO) Indicator Inoperative

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Initial Inspection and Diagnostic Overview
* Review Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions provides an overview of each diagnostic category.

Circuit/System Description

The power take-off (PTO) is an upfitter integrated system that allows the user to create an auxiliary power source. The PTO system specifically controls engine speed to values higher than normal base idle, PTO load relay engagement, and remote starting and shutdown of the engine. When the operator requests PTO using either the PTO switch or PTO remote, the engine RPM will increase to a default standby speed. The engine control module (ECM) converts the data from the engine speed sensor to a 2 pulses/engine revolution signal. When PTO is engaged, the power take-off module (PTOM) sends a GMLAN serial data message to the ECM requesting engine speeds, in accordance with the depressed switches from the PTO switch or remote.

Circuit/System Verification

1. Ignition ON, install a scan tool and verify that DTC P260D is not set as current.

- If the specified DTC is set as current, refer to DTC P260D. P260D

2. Ignition ON, with the scan tool, command the PTO Indicator ON. Observe the PTO Indicator in the PTO switch.

- If the indicator is illuminated, replace the PTO module.
- If the indicator is not illuminated, replace the PTO switch.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure. Verification Tests

* Control Module References for PTO module replacement, setup, and programming.
* Power Take-Off Switch Replacement