Engine power reduce
Nov 8, 2026 at 3:22 PM
Code P30B2?
MKAZTROL KAZTROLIE
- MEMBER
- 1 POST
Hello,
Code P30B2 – Intake Camshaft Profile Actuator Position Sensor 4 Circuit Low Voltage indicates the engine control module (ECM) has detected a voltage that is too low in the intake camshaft profile actuator position sensor circuit.
Possible causes include:
1. A faulty intake camshaft profile actuator position sensor.
2. Damaged, loose, or corroded wiring at the actuator connector.
3. A short to ground in the sensor signal circuit.
4. An electrical problem within the camshaft profile actuator assembly.
The first thing I would do is check the engine oil. If it is dirty change it out and then clear the codes.
Diagnostic information for this camshaft profile actuator system identifies sensor 4 at cylinder number 4, toward the rear of the engine. The circuit uses a 5-volt reference, a signal wire, and a low-reference circuit.
If you have a multimeter, the 5-volt reference should measure approximately 4.8 to 5.2 volts with the ignition on. Confirm the connector identification using the truck's VIN-specific wiring diagram before probing terminals.
There is also a GM service bulletin, PIT5677C, concerning engine wiring harness damage that can cause reduced engine power on 2019–2020 Sierra 1500 trucks with the 2.7L turbo engine. It is worth checking for chafed or damaged wiring.
I have two questions:
1. Is the engine the 2.7L four-cylinder turbo?
2. Does the truck run normally until the Reduced Engine Power warning appears, or is it running rough all the time?
Let me know, and we can narrow down the problem before replacing parts.
Code P30B2 – Intake Camshaft Profile Actuator Position Sensor 4 Circuit Low Voltage indicates the engine control module (ECM) has detected a voltage that is too low in the intake camshaft profile actuator position sensor circuit.
Possible causes include:
1. A faulty intake camshaft profile actuator position sensor.
2. Damaged, loose, or corroded wiring at the actuator connector.
3. A short to ground in the sensor signal circuit.
4. An electrical problem within the camshaft profile actuator assembly.
The first thing I would do is check the engine oil. If it is dirty change it out and then clear the codes.
Diagnostic information for this camshaft profile actuator system identifies sensor 4 at cylinder number 4, toward the rear of the engine. The circuit uses a 5-volt reference, a signal wire, and a low-reference circuit.
If you have a multimeter, the 5-volt reference should measure approximately 4.8 to 5.2 volts with the ignition on. Confirm the connector identification using the truck's VIN-specific wiring diagram before probing terminals.
There is also a GM service bulletin, PIT5677C, concerning engine wiring harness damage that can cause reduced engine power on 2019–2020 Sierra 1500 trucks with the 2.7L turbo engine. It is worth checking for chafed or damaged wiring.
I have two questions:
1. Is the engine the 2.7L four-cylinder turbo?
2. Does the truck run normally until the Reduced Engine Power warning appears, or is it running rough all the time?
Let me know, and we can narrow down the problem before replacing parts.
Nov 9, 2026 at 11:26 AM