P0E7B: Coolant Bypass Valve B Control Circuit/Open

P0E7B covers an interrupted control circuit of the second coolant bypass valve, B. The module sees no proper load on its output, so the valve cannot be positioned and stays wherever it last was or springs back to its rest position. Stellantis does use the valve B family: its 2025 and 2026 bulletins for the RAM 1500 and the Wagoneer with the 3.0 litre Hurricane engine list P0E7C to P0E7F together with U063C, a lost link to the valve B actuator, and its plug-in hybrids use P0E7F and P0E80. P0E7B itself appears in none of these published documents. Ford's 2019 hybrid summary shows the usual circuit test on a comparable valve, a driver fault lasting over 5 seconds. CARB requires circuit checks on such outputs. Short and plausibility faults are P0E7C to P0E7E.

Symptoms

• Check engine light
• Heating or engine warm-up behaves differently

Most likely causes

• Broken wire or unplugged connector at valve B
• Internal open in the valve B actuator
• Missing supply or ground at a networked valve actuator

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 affects emissions.

What each character of P0E7B means

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

Frequently asked questions

Can I keep driving with code P0E7B?

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 P0E7B?

The most common causes are: broken wire or unplugged connector at valve B; internal open in the valve B actuator; missing supply or ground at a networked valve actuator.

Related codes

• P0E7CCoolant Bypass Valve B Control Circuit Low
• P0E7DCoolant Bypass Valve B Control Circuit High
• P0E7ECoolant Bypass Valve B Control Circuit Range/Performance
• P0E75Coolant Bypass Valve A Control Circuit/Open
• U063CLost Communication With Coolant Bypass Valve Actuator B

Sources

• static.nhtsa.gov: MC 11038497 0001
• fordservicecontent.com: OBDSM1901 HEV
• 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.