P0E7F: Coolant Bypass Valve B Control Stuck/Open

P0E7F means coolant bypass valve B is judged to stay open while the module wants it closed. Stellantis documents it on the Chrysler Pacifica plug-in hybrid with the 3.6 litre engine: bulletin 07-008-23 (June 2023) covers cars built from 3 November 2022 to 10 February 2023, where machining debris from the cylinder head water jackets can collect inside the three-way valve. The MIL comes on and electric driving may be locked out while the petrol engine still works. To reproduce it, the bulletin has the car idle 10 minutes in engine mode, then run 5 minutes on battery with heat on and the blower below half; if P0E7F or P0E80 appears, the valve is replaced. The Hurricane software bulletins also list the code. P0E80 is the stuck closed case; P0E79 is the same fault on valve A.

Symptoms

• MIL on
• Electric drive mode unavailable, engine runs instead
• Reduced or unstable cabin heat

Most likely causes

• Machining debris lodged in the three-way coolant valve (Pacifica Hybrid, bulletin 07-008-23)
• Worn or broken internals in valve B
• Calibration issue addressed by an engine control update (3.0 Hurricane)

What to check, in order

Start with the simplest. You can tick off each step.

1. With the engine cold, check the coolant level; never do this when the system is hot
2. Check the continuity of the wire between the component and the control module.
3. Check the actual temperature in live data
4. Make sure the fan comes on when it should
5. Check the thermostat and connector
6. Measure the sensor and replace it if its readings do not make sense

Good to know

• Repair difficulty: medium
• It can trigger limp mode.
• It affects emissions.

What each character of P0E7F means

• P: Powertrain: engine and transmission
• 0: Generic code: same on every make
• E: Subsystem depends on the code range
• 7F: Specific fault in that system

Frequently asked questions

Can I keep driving with code P0E7F?

Watch the temperature gauge. If it climbs or a warning appears, stop the car in a safe place and turn off the engine: overheating can cause serious damage.

What causes code P0E7F?

The most common causes are: machining debris lodged in the three-way coolant valve (Pacifica Hybrid, bulletin 07-008-23); worn or broken internals in valve B; calibration issue addressed by an engine control update (3.0 Hurricane).

Related codes

• P0E80Coolant Bypass Valve B Control Stuck Closed
• P0E7ECoolant Bypass Valve B Control Circuit Range/Performance
• P0E79Coolant Bypass Valve A Control Stuck/Open
• U063CLost Communication With Coolant Bypass Valve Actuator B

Sources

• static.nhtsa.gov: MC 10241108 9999
• static.nhtsa.gov: MC 11038497 0001
• law.cornell.edu: 13 CCR 1968.2

Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.