P26B7 on Jeep: How to Diagnose & Fix
Engine Coolant Bypass Valve "C" Control Circuit/Open
1 Jeep model · 1 documented issue
P26B7 on Jeep by model: symptoms, diagnosis and fix
Oil found around the Pentastar oil filter adapter does not prove that the complete adapter or oil cooler has cracked. FCA's service guidance separates several repair paths: a cap O-ring that is cut, damaged, or installed in the wrong groove; five adapter bolts that are not at the specified torque; and a confirmed leak at the adapter-to-block O-rings and gaskets. FCA's 2021 guidance tells technicians to reseal a confirmed interface leak rather than replace the adapter on the covered non-2014 vehicles, while model-year 2014 is handled as an adapter-replacement exception. The previous card treated 2011-2020 vehicles alike, prescribed an aluminum assembly, implied oil/coolant cross-contamination, and listed P0128 and P26B7 without reviewed support.
Common Symptoms
- Oil visible around the oil-filter cap or adapter
- Oil collecting in the engine valley or running down the engine
- A leak that reappears in dye tracing at the adapter-to-block interface
How to Fix
Clean the area and add approved oil dye so the source can be observed before parts are ordered. Inspect the oil-filter-cap O-ring for damage and confirm it is seated in the correct groove. Check the five oil-filter-adapter bolts against FCA's 12 N-m specification and document any under-torque condition. If dye confirms a leak at the adapter-to-block interface, follow the current VIN- and model-year-specific FCA service information: the cited guidance calls for O-ring/gasket kit 68191356A$ rather than a complete adapter on covered vehicles other than model year 2014, and calls for adapter replacement on model year 2014. Transfer sensors only when the applicable replacement procedure requires it. Verify the exact suffix and current part by VIN before ordering. Do not buy a housing, cooler, seal kit, or aluminum conversion until the leak source and installed housing are confirmed.
Owner tips & cautions
- TipAsk the shop to show the dye-confirmed source: cap O-ring, adapter bolts, or the adapter-to-block interface. Those paths do not all require the same part.
- WarningDo not authorize a complete housing from oil in the valley alone. FCA specifically directs seal-only repair for a confirmed interface leak on covered non-2014 vehicles.
- WarningModel year 2014 is an exception in FCA's cited guidance. Confirm the VIN, model year, leak source, and current part suffix before ordering anything.
Sources for this issue (3)
P26B7 code reference
General diagnostic-code context. The code alone does not confirm a cause for your vehicle; use the applicable issue card and its sources.
Frequently asked questions
What does P26B7 mean on a Jeep?
P26B7 stands for "Engine Coolant Bypass Valve "C" Control Circuit/Open." This code means the engine computer detected an open (broken) electrical circuit in the control wiring for engine coolant bypass valve 'C', so it cannot properly command that valve. The coolant bypass valve controls coolant flow through the engine to even out temperatures and reduce hot spots, staying closed when cold and opening as the engine warms. If the valve cannot be controlled, the engine can overheat or have poor heater performance, so this should be addressed before it leads to overheating damage. On Jeep it is documented across 1 model: Grand Cherokee.
What are the most common causes of P26B7?
The most common causes of P26B7 are: Open or broken wiring to the coolant bypass solenoid/valve C, Faulty coolant bypass valve/solenoid (internal open), Damaged, corroded, or disconnected connector, Blown fuse or poor ground in the control circuit, Chafed harness near the engine/bellhousing area, PCM/ECM driver fault (rare). The specific cause varies by vehicle.
How much does it cost to fix P26B7 on a Jeep?
Repair costs vary widely with the root cause and Jeep model; each issue on this page carries its own estimate where one is published.
Looking for P26B7 on a different make?
View P26B7 across all makes →Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.