P260E: Diesel Particulate Filter Regeneration Lamp Control Circuit

What it means

A fault is detected in the circuit that controls the diesel particulate filter regeneration lamp. The lamp may not indicate regeneration status correctly.

At a glance

• Usually lights the check-engine light

How it works

The diesel particulate filter (DPF) regeneration lamp circuit controls an indicator that communicates regeneration status to the driver. The controller monitors that lamp circuit and sets P260E when it detects an electrical fault, so the lamp may not report regeneration status correctly. The circuit fault alone does not establish that the DPF itself is blocked, though a separate regeneration problem can cause power loss or increased fuel use.

Common causes

Most likely first.

1. Burnt-out indicator bulb
2. Open or shorted wire to the cluster

Symptoms

• Check engine light or DPF warning light on
• Power loss / limp mode
• Increased fuel consumption
• Failed forced regeneration attempts

How to diagnose it

1. Record freeze-frame data and scan for related DPF, soot-load, or regeneration codes to distinguish a lamp-circuit fault from a regeneration fault.
2. Check whether the regeneration lamp responds to the vehicle's normal lamp check or commanded test, following the manufacturer's instructions.
3. Inspect the lamp or cluster and the wiring and connectors between the cluster and controller for damage, looseness, or corrosion.
4. Test the lamp-control circuit for opens or shorts using the wiring diagram and manufacturer's procedure.
5. If the lamp circuit passes, use scan-tool data to check regeneration status and DPF-related readings before attempting any regeneration.

Common fixes

• Replace a failed DPF regeneration indicator bulb where serviceable.
• Clean and secure a loose or corroded cluster connector.
• Repair an open or shorted wire in the regeneration lamp circuit.
• Repair the cluster lamp circuit if it fails the manufacturer's test.

Can I keep driving?

A lamp-circuit fault can hide regeneration warnings, so check for separate DPF or power-loss symptoms and avoid ignoring new warning lights. If the vehicle loses power or enters limp mode, follow its DPF warning instructions and arrange prompt diagnosis.