For 1990-2009 cars

### Circuit Description

This symptom chart will aid in diagnosing a failed Power Take-Off (PTO) indicator. This diagnostic assumes that the PTO solenoid is functional and only the indicator is failing to come on. When the ignition switch is in RUN or START, voltage should be present on the Ignition 1 Voltage circuit. When the PTO switch is turned to ON, the indicator will come on. The indicator has its own ground circuit. The indicator is not necessarily lit when the PTO solenoid is engaged.

### Test Description

The number below refers to the step number on the diagnostic table.

1. This step tests the ground circuit.

Step | Action | Yes | No
--- | --- | --- | ---
Schematic Reference: Power Take-Off (PTO) Schematics
1 | Did you review the Power Take-Off Description and Operation and perform the necessary inspections? | Go to Step 2 | Go to Power Take-Off (PTO) Description and Operation
2 | Verify the fault is present. Does the system operate normally? | Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems | Go to Step 3
3 | Does the PTO solenoid engage? | Go to Step 4 | Go to Power Take-Off (PTO) Does Not Engage
4 |

1. Turn the ignition switch to RUN.
2. Ensure that the conditions for engaging the PTO solenoid are met. Refer to Power Take-Off (PTO) Description and Operation .
3. Remove the PTO switch but leave it connected to the harness.
4. Turn the PTO switch to the ON position.
5. Connect a fused jumper wire at the PTO switch connector ground circuit to a known ground.

Does the indicator come on?

Go to Step 5

Go to Step 6

5 | Repair the open or high resistance in the ground circuit. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 7 | --
6 | Replace the PTO switch. Refer to Upfitters instructions. Did you complete the replacement? | Go to Step 7 | --
7 | Test drive the vehicle and operate the PTO system as described in the supporting test. Does the symptom occur? | Go to Step 3 | System OK