# Service bulletin 18\-023\-26

A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.

- Type: Service bulletin
- NHTSA id: 11029678
- Published by NHTSA: 2026\-03\-05
- Manufacturer's number: 18\-023\-26
- Manufacturer's date: 2026\-02\-18
- NHTSA component: ELECTRICAL SYSTEM; ENGINE

## NHTSA's summary

Flash: Powertrain Control Module \(PCM\) Updates \*\*Customers must experience a Malfunction Indicator Lamp \(MIL\) illumination and the vehicle must SYMPTOM: exhibit/set one or more of the following Diagnostic Trouble Codes \(DTCs\): ● P0128\-00 \- Thermostat Rationality. ● P24A4\-00 \- Particulate Filter Restriction \- Soot Accumulation Too High. ● P208B\-00 \- Reductant Pump 1 Control Performance.\*\* Customers may experience one or more of the following: ● Lower than expected fuel economy when vehicle is lightly loaded, operating in stop and go traffic and at lower speeds. ● Long cranking / extended starting times. \*\*Other software enhancement included with this update: ● "Air Handling Performance Test" is now available to help troubleshoot air handling DTCs.\*\* This bulletin involves reprogramming the PCM with the latest available software.

## The document

- [NHTSA's copy of the document (PDF)](https://static.nhtsa.gov/odi/tsbs/2026/MC-11029678-0001.pdf)
- [If that address does not open, try this one](https://static.nhtsa.gov/odi/tsbs/2026/MC-11029678-9999.pdf)

The document is the manufacturer's. This site does not hold it.

## Components

Electrical system, Engine

## Trouble codes named

P0128, P208B, P24A4

## Vehicles listed

- 2023 RAM 4500
- 2023 RAM 5500

## Recalls for the same vehicles and component

- [2023026](/recalls/tc/2023026.md), 2023-02-09: Electrical
- [23V060000](/recalls/nhtsa/23V060000.md), 2023-02-09: ELECTRICAL SYSTEM:WIRING:RELAYS/SOLENOIDS

## Other bulletins for the same vehicles and component

- [114254](/bulletins/11036754.md), 2026-09-03, Service bulletin: ENGINE. RADIATOR \- ENGINE COOLING
- [114255](/bulletins/11036753.md), 2026-09-03, Service bulletin: ENGINE. RADIATOR \- ENGINE COOLING
- [113855](/bulletins/11036364.md), 2026-08-26, Service bulletin: STRUCTURE:BODY; ELECTRICAL SYSTEM. SWITCH AND BEZEL \- FRONT DOOR
- [113854](/bulletins/11036363.md), 2026-08-26, Service bulletin: ELECTRICAL SYSTEM; STRUCTURE:BODY. SWITCH AND BEZEL \- FRONT DOOR
- [113744](/bulletins/11035981.md), 2026-08-06, Service bulletin: ENGINE; ELECTRICAL SYSTEM. SENSOR \- TURBOCHARGER SPEED
- [113742](/bulletins/11035980.md), 2026-08-06, Service bulletin: ENGINE; ELECTRICAL SYSTEM. SENSOR \- TURBOCHARGER SPEED
- [08\-272\-26 REV. A](/bulletins/11035162.md), 2026-07-23, Service bulletin: ELECTRICAL SYSTEM. Air Handling Performance Test \(APT\) Availability In wiTECH Technicians may experience a Malfunction Indicator Lamp \(MIL\) illumination and the vehicle may SYMPTOM: exhibit/set one or more of the following Diagnostic Trouble Codes \(DTCs\): ● P0234\-00 \- Turbocharger Overboost Condition. ● P0299\-00 \- Turbocharger Underboost. ● P0101\-00 \- Mass Air Flow Sensor "A" Circuit Performance. ● P2463\-00 \- Diesel Particulate Filter Restriction \- Soot Accumulation Bank 1. ● P24A4\-00 \- Particulate Filter Restriction \- Soot Accumulation Too High. ● P2262\-00 \- Turbocharger Boost Pressure Not Detected \- Mechanical. ● P0471\-00 \- Exhaust Pressure Sensor 1 Performance. ● P1451\-00 \- Diesel Particulate Filter System Performance. ● P2457\-00 \- Exhaust Gas Recirculation Cooling System Performance. ● P2263\-00 \- Turbo Boost System Performance. ● P2459\-00 \- Diesel Particulate Filter Regeneration Too Frequent. ● P24A2\-00 \- Diesel Particulate Filter Regeneration Incomplete \- Bank 1. ● P0401\-00 \- EGR System Performance. ● P0402\-00 \- EGR Flow Excessive Detected.
- [113293](/bulletins/11035080.md), 2026-07-18, Service bulletin: ENGINE. INJECTOR \- FUEL
- [113292](/bulletins/11035073.md), 2026-07-18, Service bulletin: ENGINE. INJECTOR \- FUEL
- [9100803 Rev 3](/bulletins/11035065.md), 2026-07-18, Service bulletin: STRUCTURE:BODY; ELECTRICAL SYSTEM. Front Fog Lamp RT 1\) If the lamp contains moisture, do not replace it immediately. Turn the fog lamp on for one hour and inspect it afterward. Refer to 23\-008\-25 Rev.A. Exterior Front Lamps Condensation Clearing Procedure for details. 2\) If the fog lamp\(s\) do not light. Refer to Star Online Publication S2523000085 for details.

JSON: [/v1/bulletins/11029678](/v1/bulletins/11029678)

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