Circuit Description
The DTC P1690 Rocker Arm Actuator Solenoid Control Circuit diagnostic monitors the electrical circuit of the rocker arm oil control solenoid. The rocker arm oil control solenoid enables the powertrain control module (PCM) to operate the high speed cam system. The high speed cam system significantly increases valve lift at engine speeds above 6,000 RPM. A second camshaft lobe with a high lift profile is cast into each camshaft, alongside the low/medium speed lobes. Unique rocker arms follow both the high speed and low/medium speed cam lobes. At engine speeds below 6,000 RPM, the low/medium speed cam lobes operate the rocker arms. When the rocker arm oil control solenoid is turned ON between 6,000-8,200 RPM, the rocker arms are operated by the high speed cam lobes. The rocker arm oil control solenoid is controlled by a pulse width modulated (PWM) signal from the PCM. A fault in the solenoid control circuit will set a DTC P1690. For additional information on the operation of the rocker arm oil control system refer to Rocker Arm Oil Control System Description .
Conditions for Running the DTC
The ignition is ON.
Conditions for Setting the DTC
The PCM detects an open or a short in the control circuit of the rocker arm oil control solenoid.
Action Taken When the DTC Sets
| • | The PCM illuminates the malfunction indicator lamp (MIL). |
| • | The PCM stores the conditions that were present when the DTC set as Freeze Frame data. |
Conditions for Clearing the MIL/DTC
| • | The PCM turns OFF the MIL on the third consecutive trip cycle during which the diagnostic has been run and the fault condition is no longer present. |
| • | A DTC clears after 40 consecutive warm-up cycles have occurred without a fault. |
| • | A DTC can be cleared by using the scan tool Clear DTC Information function. |
Test Description
The numbers below refer to the step numbers in the diagnostic table.
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The Diagnostic System Check-Engine Controls prompts the technician to complete some basic checks and store the Freeze Frame data on the scan tool if applicable. This creates an electronic copy of the data taken when the fault occurred. The information is then stored in the scan tool for later reference.
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This step checks the operation of the rocker arm oil control solenoid. This inspection is to be performed when the vehicle is at normal operating temperature with the engine speed at 1,500-2,500 RPM. Turning ON the rocker arm oil control solenoid will increase valve lift enough to cause a significant drop in engine speed.
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This step checks for electrical resistance in the wiring and connections of the rocker arm oil control solenoid circuit. Circuit resistance as small as 45 ohms can cause a DTC P1690 to set.
Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: Engine Controls Schematics | |||
Did you perform the Diagnostic System Check-Engine Controls? | Go to Step 2 | ||
2 |
Is DTC P1690 set? | Go to Step 4 | Go to Step 3 |
3 |
Does the engine idle very rough or stall when the rocker arm oil control solenoid is commanded ON? | Go to Intermittent Conditions | Go to Step 4 |
Does the engine idle very rough or stall when the rocker arm oil control solenoid is connected to B+? | Go to Step 5 | Go to Step 8 | |
5 |
Was a repair necessary? | Go to Step 6 | Go to Step 7 |
6 |
Was a repair necessary? | Go to Step 11 | Go to Step 9 |
7 |
Was a repair necessary? | Go to Step 11 | Go to Step 9 |
8 | Replace the rocker arm oil control solenoid. Refer to Rocker Arm Oil Control Solenoid Valve Replacement . Is the action complete? | Go to Step 11 | -- |
Was a repair necessary? | Go to Step 11 | Go to Step 10 | |
10 | Replace the PCM. Refer to Powertrain Control Module Replacement . Is the action complete? | Go to Step 11 | -- |
11 |
Does the DTC run and pass? | Go to Step 12 | Go to Step 2 |
12 | With a scan tool, observe the stored information, Capture Info. Does the scan tool display any DTCs that you have not diagnosed? | System OK | |
