Circuit Description
The crankshaft position (CKP) sensor A is a 24X sensor and contains a hall-effect switch. This solid state switching device produces 24 digital ON/OFF pulses per engine revolution. These pulses occur when the interrupter ring, mounted to the crankshaft damper assembly and containing 24 evenly spaced blades and windows, passes between the sensor tip and a magnet. The 24X sensor is connected directly to the powertrain control module (PCM). The PCM provides 12 volts to the sensor on a 12-volt reference circuit, and provides a ground on a low reference circuit. The PCM receives the pulses from the sensor on the medium resolution engine speed signal circuit. The PCM uses the 24X signal for enhanced smoothness and idle stability at lower engine speeds. The PCM monitors the CKP sensor A for errors. If the PCM does not receive a signal from the CKP sensor A, DTC P0335 sets.
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC P0335 Crankshaft Position (CKP) Sensor A Circuit
Conditions for Running the DTC
| • | The engine is running for more than 3 seconds. |
| OR |
| • | The engine is cranking. |
| • | DTC P0335 runs continuously when either condition is met. |
Conditions for Setting the DTC
| • | The PCM detects the following for every 2 engine revolutions: |
| - | Six low resolution engine speed signals |
| - | One camshaft position (CMP) sensor signal |
| - | Zero medium resolution engine speed signals |
| • | The conditions are met for more than 8 seconds. |
Action Taken When the DTC Sets
| • | The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails. |
| • | The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records. |
Conditions for Clearing the MIL/DTC
| • | The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail. |
| • | A current DTC, Last Test Failed, clears when the diagnostic runs and passes. |
| • | A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic. |
| • | Clear the MIL and the DTC with a scan tool. |
Diagnostic Aids
DTC P0335 can be caused by secondary components leaking high voltage into the ignition control module (ICM). Inspect for the following conditions:
| • | Incorrect harness routing near the secondary ignition components |
| • | Ignition coil arcing to wiring harness or ignition control (IC) module--Inspect ignition coils for cracks, for carbon tracking, or for other signs of damage. |
| • | Secondary ignition wires arcing to the wiring harness |
| • | If the DTC is determined to be intermittent, refer to Intermittent Conditions . |
Test Description
The number below refers to the step number on the diagnostic table.
Step | Action | Values | Yes | No |
|---|---|---|---|---|
Schematic Reference: Engine Controls Schematics Connector End View Reference: Engine Controls Connector End Views or Powertrain Control Module Connector End Views | ||||
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information |
2 |
Does 24X RPM vary with engine speed up to approximately 1,600 RPM? | -- | Go to Step 3 | Go to Step 4 |
3 |
Does the DTC fail this ignition? | -- | Go to Step 4 | Go to Diagnostic Aids |
4 |
Is the voltage measured within 1 volt of the specified value? | B+ | Go to Step 5 | Go to Step 9 |
5 | Measure the voltage from the 12-volt reference circuit to the low reference circuit of the CKP sensor A, with the DMM. Is the voltage measured within 1 volt of the specified value? | B+ | Go to Step 6 | Go to Step 10 |
6 |
Is the amperage more than the specified value? | 210 mA | Go to Step 7 | Go to Step 11 |
Does the 24X RPM change each time the signal circuit is touched? | -- | Go to Step 16 | Go to Step 8 | |
8 | Did the test lamp illuminate? | -- | Go to Step 14 | Go to Step 13 |
9 | Test the 12-volt reference circuit of the CKP sensor A for an open or a short to ground. Refer to Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 19 | Go to Step 15 |
10 | Test the low reference circuit of the CKP sensor A for an open. Refer to Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 19 | Go to Step 15 |
11 | Test the 12-volt reference circuit of the CKP sensor A for high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 19 | Go to Step 12 |
12 | Test the low reference circuit of the CKP sensor A for high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 19 | Go to Step 15 |
13 | Test the medium resolution engine speed signal circuit of the CKP sensor A for an open or for a short to voltage. Refer to Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 19 | Go to Step 15 |
14 | Test the medium resolution engine speed signal circuit of the CKP sensor A for a short to ground. Refer to Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 19 | Go to Step 15 |
15 | Test for an intermittent or poor connection at the powertrain control module (PCM). Refer to Testing for Continuity and Testing for Intermittent Conditions and Poor Connections in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 19 | Go to Step 17 |
16 | Test for an intermittent or poor connection at the 24X CKP sensor A. Refer to Testing for Continuity and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 19 | Go to Step 18 |
17 | Replace the PCM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming. Did you complete the replacement? | -- | Go to Step 19 | -- |
18 | Replace CKP sensor A. Refer to Crankshaft Position Sensor Replacement . Did you complete the replacement? | -- | Go to Step 19 | -- |
19 |
Did the DTC fail this ignition? | -- | Go to Step 2 | Go to Step 20 |
20 | Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed? | -- | Go to Diagnostic Trouble Code (DTC) List - Vehicle in Vehicle DTC Information | System OK |
