P242B
0 owner reports and 34 manufacturer filings across 8 model years from Chevrolet, GMC, Ram.
Where P242B shows up
Source: NHTSA manufacturer communications and complaints| Model year | Filed under | Bulletins | Owner reports |
|---|---|---|---|
| 2024 Chevrolet Silverado 2500HD | Engine | 6 | — |
| 2024 Chevrolet Silverado 3500HD | Engine And Engine Cooling | 6 | — |
| 2024 GMC Sierra 2500HD | Engine | 6 | — |
| 2024 GMC Sierra 3500HD | Electrical System | 6 | — |
| 2026 Ram 3500 | Electrical System | 3 | — |
| 2025 Ram 3500 | Electrical System | 3 | — |
| 2026 Ram 2500 | Electrical System | 2 | — |
| 2025 Ram 2500 | Electrical System | 2 | — |
A model year appears here because the code is named in its record, not because every one of these vehicles sets it. Counts are mentions in the federal files, not failure rates — nobody publishes the denominator.
What it gets filed under
Manufacturer filings that name it
Source: NHTSA manufacturer communicationsService bulletins and campaigns whose filed summary names P242B. Quoting the document number at a service desk is often the fastest route to a diagnosis someone has already written down.
- S26250000042026-03-31 · Electrical System
- Active/Pending Diagnostic Trouble Code (DTC) P24A0, P2482, P2481, P0420, P2470, P2471, P2472, P242D, P242B, P244D, P1484 And/or P214D setting In The Powertrain Control Module (PCM)
- S26250000032026-03-31 · Electrical System
- Active/Pending Diagnostic Trouble Code (DTC) P24A0, P2482, P2481, P0420, P2470, P2471, P2472, P242D, P242B, P244D, P1484, P106D, P1060 And/or P354B Setting In The Powertrain Control Module (PCM)
- OTHERDOC_147 Over-the-air update2025-09-05 · Electrical System
- Powertrain Contol Module Over The Air Update to V2B (Diesel Only) Software Version (FOTA) 2025 - 2026 (DJ) RAM 2500 Pickup 2025 - 2026 (D2) RAM 3500 Pickup 2025 - 2026 (DD) RAM 3500 Cab Chassis 2025 - 2026 (DF) RAM 3500 10K Lb. Cab Chassis2025 - 2026 (DP) RAM 4500/5500 Cab Chassis Customers may experience one or more of the following: - Power Inverter (110V connection) drops out when shifting from
- 23-NA-0662024-05-24 · Engine
- This service bulletin refers the technician to Recall N242438501, and if closed, refer to SI to correct the condition of Malfunction Indicator Lamp Illuminated with DTCs P0402, P062D, P144E, P242B, P2459, and/or P2635 Set.
- 23-NA-0662024-04-16 · Electrical System
- This service bulletin provides a procedure to correct the condition of Malfunction Indicator Lamp Illuminated with DTCs P0402, P062D, P144E, P242B, P2459, and/or P2635 Set.
- 23-NA-0662023-12-14 · Electrical System
- This service bulletin provides a procedure to correct the condition of Malfunction Indicator Lamp Illuminated with DTCs P0402, P062D, P144E, P242B, P2459, and/or P2635Set.
What P242B means
Source: SAE J2012 / OBD-IIP242B sits in the generic range of the OBD-II standard, so it means the same thing on every vehicle sold in the United States — but WhichTrim does not carry a definition for it and will not invent one. What is on this page is the record: who named it and on what.
A stored code names the test that failed, never the part that caused it. It is the starting point of a diagnosis, not its conclusion — the same code has several possible causes and the cheap one is not always right.
Common questions about P242B
Source: NHTSA files and the OBD-II standardCan I keep driving with P242B stored?
Nobody can answer that from the code alone, and a site that does is guessing. A steady light generally means the fault was logged and the vehicle is in a reduced-risk mode; a flashing light means stop soon, because a misfiring engine can destroy a catalytic converter in minutes. The safe read of this page is the mileage and the components, not permission.
Does a code mean the car is recalled?
No. Recalls are filed by campaign and matched by VIN, and none of them are triggered by a scan tool. If you want to know whether an open recall applies to one specific vehicle, check the VIN at nhtsa.gov/recalls — that is the only source that settles it.
Why do the counts here differ from other sites?
Because these are not estimates. Every number on this page is a count of documents in NHTSA's own files: manufacturer communications that name the code in their filed summary, and owner complaints that name it in the narrative. We do not model, weight or extrapolate them.
Will clearing the code fix it?
Clearing turns the light off and erases the freeze-frame data a technician would have used to work out what happened. If the condition is still there the code returns, usually within a few drive cycles, and the diagnosis now starts from less information than before.