P2595: Turbocharger Speed Sensor B Circuit Low

P2595 is logged when the signal of turbocharger speed sensor B stays below the range the engine computer accepts, as with a short to ground or a sensor whose output has collapsed. Bentley names it for the W12 in Continental GT, GTC and Flying Spur from 2018 and later also in the Bentayga, stored in engine control unit 1 or 2. Unlike the plausibility code P2594, which may first be cleared and retested, the bulletin goes straight to the replacement of the affected sensor (G688 or G689) once wiring tests for opens and shorts pass; on the Bentayga the bank 1 sensor is much harder to reach. The opposite electrical fault is P2596, sensor A reports the same condition as P2580.

Symptoms

• Malfunction indicator lamp on
• Speed of the second turbo shown as zero or very low
• Possible reduction of boost

Most likely causes

• Speed sensor B with collapsed output
• Signal wire of sensor B shorted to ground
• Corroded or contaminated connector at sensor B

What to check, in order

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

1. Check the hoses, clamps, and intercooler
2. With the connector unplugged, check whether the signal wire is making contact with ground.
3. Compare commanded and actual pressure in live data
4. Check the actuator's movement
5. Check the vacuum hoses and the solenoid valve
6. Check the oil and the turbo shaft play before replacing it

Good to know

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

What each character of P2595 means

• P: Powertrain: engine and transmission
• 2: Generic code: same on every make
• 5: Speed and idle
• 95: Specific fault in that system

Frequently asked questions

Can I keep driving with code P2595?

Drive without demanding power and go to a repair shop soon. If you see a lot of blue smoke or hear a metallic noise, shut off the engine.

What causes code P2595?

The most common causes are: speed sensor B with collapsed output; signal wire of sensor B shorted to ground; corroded or contaminated connector at sensor B.

Related codes

• P2593Turbocharger Speed Sensor B Circuit
• P2594Turbocharger Speed Sensor B Circuit Range/Performance
• P2596Turbocharger Speed Sensor B Circuit High
• P2597Turbocharger Speed Sensor B Circuit Intermittent
• P2580Turbocharger/Supercharger Speed Sensor A Circuit Low

Sources

• static.nhtsa.gov: MC 10203225 0001
• static.nhtsa.gov: MC 10228850 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.