2010 Cadillac Truck SRX FWD V6-3.0L Page 1448

2010 Cadillac Truck SRX FWD V6-3.0L Page 1448

Circuit/System Description

The 4X camshaft position sensor circuits consist of an engine control module (ECM) supplied 5 V reference circuit, low reference circuit, and an

output signal circuit. The camshaft position sensor is an internally magnetic biased digital output integrated circuit sensing device. The sensor

detects magnetic flux changes of the teeth and slots of a 4-tooth reluctor wheel attached to the camshaft. As each reluctor wheel tooth rotates past

the camshaft position sensor, the resulting change in the magnetic field is used by the sensor electronics to produce a digital output pulse. The

sensor returns a digital ON/OFF DC voltage pulse of varying frequency, with 4 varying width output pulses per camshaft revolution that represent

an image of the camshaft reluctor wheel. The frequency of the camshaft position sensor output depends on the velocity of the camshaft. The ECM

decodes the narrow and wide tooth pattern to identify camshaft position. This information is then used to determine the optimum ignition and

injection points of the engine. The ECM uses the cylinder 1 intake camshaft position sensor to determine injector and ignition system

synchronization. Also, the cylinder 1 intake camshaft position sensor is used to determine camshaft to crankshaft relationship, to control camshaft

phasing, and for limp-home operation.

Conditions for Running the DTC

* DTCs P0335, P0336, P0641, P0651, or P0697 are not set.

* The engine is cranking or running.

* The DTC runs continuously when the above conditions are met.

Conditions for Setting the DTC

* The ECM detects that the engine has started, but has received either of the following during the first engine revolution:

- Less than or more than 4 camshaft position sensor pulses, if equipped with an automatic transmission

- Less than 4 or more than 8 camshaft position sensor pulses, if equipped with a manual transmission

* The ECM detects that the engine is running, but receives less than 398 camshaft position or more than 402 camshaft position sensor pulses

per 100 engine cycles in 800 of 1000 engine cycles.

Action Taken When the DTC Sets

* DTCs P0341, P0346, P0366, and P0391 are Type B DTCs.

* The camshaft position actuator is commanded to the Home or Parked position.

* The ignition system defaults to a failed camshaft position sensor based on the crankshaft position sensor.

Conditions for Clearing the MIL/DTC

* DTCs P0341, P0346, P0366, and P0391 are Type B DTCs.

* With a DTC set, the engine may crank for an extended period of time at start-up.

Diagnostic Aids

* With a DTC set, the engine may crank for an extended period of time at start-up.

* The cylinder 1 intake camshaft position sensor is used for injector and ignition system synchronization. A stalling condition will occur if the

CMP sensor signal is intermittent and a DTC will not set. Inspect all cylinder 1 intake camshaft position sensor circuits for poor connections.

Reference Information

Schematic Reference

Engine Controls Schematics (LAU) (See: Diagrams/Electrical Diagrams/Powertrain Management/System Diagram)Engine Controls Schematics

(LF1) (See: Diagrams/Electrical Diagrams/Powertrain Management/System Diagram)

Connector End View Reference

Component Connector End Views (See: Diagrams/Connector Views/Connector End Views By Name)

Description and Operation

Electronic Ignition System Description (See: Powertrain Management/Computers and Control Systems/Description and Operation/Electronic

Ignition System Description)

Electrical Information Reference

* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit

Testing/Circuit Testing)

* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic

Procedures/Connector Repairs/Connector Repairs)

* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General

Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)

* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring

Repairs/Wiring Repairs)