P2474 – DPF Temperature Sensor Circuit Low (Bank 2 Sensor 4)

System: Powertrain | Standard: ISO/SAE Controlled | Fault type: Circuit Low | Location: Bank 2, Sensor 4

Definition source: SAE J2012/J2012DA (industry standard)

P2474 indicates the powertrain control module has detected a low electrical input in the diesel particulate filter (DPF) temperature sensor circuit identified as Bank 2 Sensor 4. “Circuit low” is an electrical fault classification and points toward a signal that is lower than expected for the operating conditions, rather than confirming a clogged DPF or a bad sensor by itself. How the sensor is named, where it is located, what readings are expected, and when the code sets can vary by vehicle, so always verify component identification, pinouts, and test specs using the correct service information.

What Does P2474 Mean?

P2474 – DPF Temperature Sensor Circuit Low (Bank 2 Sensor 4) means the control module detected that the DPF temperature sensor circuit for the specified sensor position is reporting an abnormally low input. Under SAE J2012 DTC conventions, this is treated as a circuit low condition, commonly associated with an unwanted path to ground, loss of power/feed to the sensor circuit, excessive resistance causing a voltage drop, damaged wiring, connector problems, or an internal sensor fault that pulls the signal low. The code identifies an electrical/signal problem; it does not, by itself, prove a specific exhaust temperature or DPF condition.

Quick Reference

• System: Powertrain
• Official meaning: DPF Temperature Sensor Circuit Low (Bank 2 Sensor 4)
• Standard: ISO/SAE controlled
• Fault type: Circuit Low
• Severity: MIL illumination is possible; some vehicles may reduce regeneration capability or power output to protect the aftertreatment system.

Symptoms

• MIL/Warning lamp: Check engine light illuminated and P2474 stored as current or pending.
• Regeneration behavior: Regeneration may be inhibited, delayed, or commanded more/less often than expected depending on strategy (varies by vehicle).
• Reduced power: Limited torque or reduced power mode may occur if aftertreatment protection logic is triggered.
• Driveability changes: Hesitation or sluggish response can occur if fueling/aftertreatment control is altered as a safeguard.
• Fuel economy: Increased fuel consumption if control strategy compensates for unreliable temperature feedback.
• Exhaust odor/smoke: Changes may be noticed if aftertreatment operation is affected, though this is not diagnostic on its own.
• Additional codes: Related temperature sensor, heater, or aftertreatment efficiency/regeneration codes may also be present.

Common Causes

• Short to ground on the signal circuit: Chafed insulation or pinched harness pulling the sensor signal low.
• Open power/feed to the sensor: Loss of supply voltage (where applicable) causing the circuit to read low.
• High resistance in the power or ground path: Corrosion, damaged conductors, or poor splices creating voltage drop that results in a low input.
• Connector issues at the sensor: Water intrusion, terminal corrosion, poor pin fit, bent pins, or a partially unseated connector.
• Connector issues at the control module: Backed-out terminals, fretting, or corrosion on the corresponding circuit pins.
• Harness damage near heat sources: Melted loom or brittle wiring close to exhaust/aftertreatment components leading to shorts or opens.
• Faulty DPF temperature sensor: Internal sensor fault that biases the output low or loads the circuit.
• Improper repairs: Incorrect wire gauge, poor crimping, or misrouted harness causing intermittent contact or repeated damage.

Diagnosis Steps

Tools you’ll typically need include a scan tool capable of reading live data and freeze-frame, a digital multimeter, and back-probing or breakout leads to avoid damaging terminals. Service information is required for connector pinouts, wiring colors, and circuit descriptions that vary by vehicle. If available, use a wiring diagram and a test light or fused jumper for controlled circuit loading checks.

1. Confirm the code and capture data: Verify P2474 is present, record freeze-frame data, and note any related aftertreatment or sensor circuit DTCs. Address battery/charging or module voltage codes first if present.
2. Check for repeatability: Clear codes, then run the conditions needed for the monitor to execute (varies by vehicle). If it resets immediately, suspect a hard electrical fault (short/open).
3. Review live data for the sensor input: Observe the DPF temperature sensor parameter associated with Bank 2 Sensor 4. A fixed low reading or a value that does not respond to operating changes supports a circuit-low condition, but do not condemn parts without circuit testing.
4. Perform a visual inspection: With the engine off and cool as needed, inspect the harness routing to Bank 2 Sensor 4 for abrasion, melted insulation, crushed sections, or contact with exhaust components. Inspect the sensor connector for locks fully seated and for contamination or corrosion.
5. Connector integrity checks: Unplug the sensor and inspect terminals for bent pins, spread terminals, or backed-out terminals. Verify terminal tension (pin fit) by gently checking for looseness; repair terminal issues before deeper electrical testing.
6. Wiggle test with live logging: Reconnect as appropriate and log the sensor signal while gently manipulating the harness and connector at the sensor and along the run to the control module. Any dropouts or sudden low excursions indicate an intermittent connection or insulation damage.
7. Check for short-to-ground on the signal circuit: Key off, disconnect the sensor and the control module connector for the affected circuit if service information recommends it. Measure resistance/continuity between the signal wire and chassis ground. Continuity suggests a short to ground; isolate by segmenting the harness and inspecting the contact point.
8. Verify power/feed and ground availability: With key on (engine off) and connectors attached as required by the test method, verify the sensor’s supply/feed circuit and ground circuit integrity per service information. If either is missing or weak, trace back to the source, splice, fuse, relay, or ground point as applicable.
9. Voltage-drop test under load: Perform voltage-drop testing on the sensor power and ground paths while the circuit is powered (and with an appropriate load if specified). Excessive drop indicates high resistance from corrosion, damaged conductors, or poor splices that can drive the input low.
10. Signal circuit continuity and resistance checks: With key off and the relevant connectors disconnected, check continuity end-to-end on the signal circuit and check for unwanted continuity to other circuits. Repair opens, high resistance, or cross-shorts found.
11. Component isolation test: If wiring tests pass, evaluate the sensor by following service information to confirm it isn’t internally pulling the circuit low. If substituting a known-good sensor is an approved method, use it to confirm before replacement.
12. Verify the repair: After repairs, clear codes and perform a complete drive cycle or enable criteria run so the monitor can execute. Recheck for pending codes and confirm the live data behaves plausibly without dropping low during a final wiggle test.

Professional tip: A “circuit low” code is often caused by harness damage near heat and sharp edges. Before replacing any component, prioritize finding shorts-to-ground and voltage drops at connectors; a quick back-probe inspection plus a loaded voltage-drop test can expose high-resistance faults that continuity checks alone may miss.

Possible Fixes & Repair Costs

Repair costs for P2474 can vary widely because the underlying issue may be as simple as a connector problem or as involved as harness repair or sensor replacement. Total expense depends on diagnostic time, parts availability, and how accessible the sensor and wiring are on your vehicle.

• Repair wiring faults: Locate and repair short-to-ground, chafed insulation, crushed sections, or damaged conductors in the DPF temperature sensor (Bank 2 Sensor 4) signal and return circuits.
• Restore power/ground integrity: Clean and secure ground points, repair open feeds, and correct high-resistance connections found during voltage-drop testing.
• Connector service: Clean contamination, remove corrosion, correct moisture intrusion, and address loose/poor pin fit at the sensor and related harness connectors; replace terminals/connectors as needed.
• Replace the DPF temperature sensor: Replace only after confirming the circuit is healthy and the sensor output remains low under proper electrical conditions.
• Harness routing correction: Re-route and re-secure the harness to prevent future contact with hot or moving components that can cause insulation damage and repeated circuit-low faults.
• ECM/PCM checks: If all external wiring and the sensor test good, follow service information to verify controller-side input integrity and connector pin condition; replacement is rare and should be proven by testing.

Can I Still Drive With P2474?

You may be able to drive with P2474, but it’s best to limit operation until the fault is diagnosed because a circuit-low signal from the DPF temperature sensor can cause the control module to alter emissions strategies and, on some vehicles, reduce engine power or inhibit certain functions. If you notice reduced power, severe drivability issues, warning messages related to powertrain control, or any signs of stalling/no-start, do not continue driving—arrange service and verify the issue with appropriate testing and service information.

What Happens If You Ignore P2474?

Ignoring P2474 can lead to persistent warning lights, repeated fault storage, and continued incorrect DPF temperature feedback to the control module. Over time, that can contribute to degraded emissions control performance and may trigger additional related codes or operating limits, depending on vehicle strategy. The underlying electrical issue (such as chafed wiring or corrosion) can worsen and become harder to repair if left unaddressed.

Last updated: February 17, 2026

Vehicles Commonly Affected by P2474

• Vehicles equipped with a diesel particulate filter using multiple exhaust temperature sensors for DPF monitoring.
• Powertrains with Bank 2 exhaust layouts where “Bank 2 Sensor 4” is a defined sensor position in service information.
• Applications with underbody sensor routing where harnesses are exposed to heat, road debris, and moisture.
• Vehicles with sensor connectors near the exhaust prone to thermal cycling, terminal tension loss, or contamination.
• Trucks and commercial-duty platforms that experience vibration and long operating hours, increasing wiring fatigue risk.
• Stop-and-go duty cycles that increase heat cycling and condensation exposure at exhaust connectors.
• Vehicles operating in corrosive environments where road salt or water intrusion can affect terminals and grounds.
• Vehicles with recent exhaust or aftertreatment work where connectors may be left loose, misrouted, or pinched (varies by vehicle and repair history).

Always verify sensor location and circuit identification for “Bank 2 Sensor 4” using the correct service information for your vehicle before testing or replacing any components.