“A” Camshaft Position Actuator Circuit (Bank 1)
Note: The “A” identifies the intake camshaft, which is located to the intake side of the cylinder head. “Bank 1” denotes the engine bank that contains the number one cylinder.
This indicates that a fault has been detected in the Electronic Variable Valve Timing (VVT) or Electronic Variable Camshaft Timing (VCT) circuit voltage for engine bank 1.
Code Set Parameters
Variations in timing between the camshaft/s and the crankshaft that exceed 10-degrees of the reference value (with engine idling) will initiate a stored PCM code. A low voltage reading in the system electrical circuit will cause a trouble code to be stored.
Symptoms which accompany the service engine light include roughness when accelerating with reduced fuel economy and engine performance. A code will be stored in the PCM and a malfunction indicator lamp will be illuminated.
Possible causes include a faulty oil control valve (OCV), a short or open circuit in the VVT, OCV, or VCT circuits, or a low oil level/pressure condition.
Failure of system components (including the PCM) is rare. Open or shorted electrical circuits are slightly more common but often camshaft and/or crankshaft sensors are replaced when a low oil pressure/level condition is the culprit.
- Begin your diagnosis by visually inspecting all wiring and connectors
- Look for shorted or burned wiring and replace circuitry and connectors as required
If the system wiring, connectors, and components appear to be in normal working order, connect the scanner to the diagnostic connector and record all stored trouble codes and freeze frame data
- This information can be extremely helpful in diagnosing intermittent conditions that may have contributed to this code being stored
- After the codes are cleared, operate the vehicle to see if the code returns
- If the code fails to immediately return, you may have an intermittent condition
- Intermittent conditions can prove to be quite a challenge to diagnose and in extreme cases may have to be allowed to worsen before a correct diagnosis can be made.
Testing of the system electrical wiring, using a voltage drop method with battery voltage as a reference point, normally yields a correct diagnosis
- Low mileage component failure is rare with the likelihood of such increasing as mileage increases
- Since several timing components utilize oil pressure for proper operation, most malfunctions can be attributed to low oil pressure/level
- Crankshaft and camshaft positions are monitored using electromagnetic sensors
- These sensors utilize relief holes in camshaft and crankshaft drive gears to provide signal interruption in the electromagnetic field
- Some manufacturers use multiple crankshaft sensors to feed separate data streams to the PCM
- Typically, these data streams provide input for engine ignition and fuel injection timing
- Engines that are equipped with multiple camshafts generally use a camshaft sensor for each camshaft
- Other automakers use notches cut into shafts or nodules that are permanently attached to interrupt the electromagnetic field
- Often these notches or nodules are located near the rear or middle of the shaft, depending upon sensor placement
- One manufacturer even places the crankshaft sensor on top of the transmission bell-housing and reads crankshaft position from interrupter holes in the flex plate.