P0077 - Intake Valve Control Solenoid Circuit High (Bank 1)
System
Powertrain (Engine & Gearbox)
Technical Description
The control module has detected a fault in the Intake Valve Control Solenoid Circuit High (Bank 1) (P0077). The signal is above the upper threshold, typically from an open circuit, poor connection, or a short to battery voltage. Affects cylinder bank 1 (bank 1 containing cylinder 1, firewall/right side).
Multimeter Test Points & Nominal Values
| Test Point / Component | Measurement | Nominal Target Range | Test Condition |
|---|---|---|---|
| Intake Valve Control Solenoid Circuit High (Bank 1) – Coil Resistance | Resistance (Ω) | 20 - 120 Ω (relay) / 8 - 40 Ω (solenoid) | Device disconnected at 20°C |
| Intake Valve Control Solenoid Circuit High (Bank 1) – Supply Voltage | Voltage (V) | 11.8 - 14.4 V | Ignition ON, high side of load |
| Intake Valve Control Solenoid Circuit High (Bank 1) – Control (Low Side) Rest / Active | Voltage (V) | Rest ≈ battery voltage / Active < 1.0 V | Module commanding device ON/OFF |
Device disconnected at 20°C
Ignition ON, high side of load
Module commanding device ON/OFF
Oscilloscope Waveform Analysis
5 ms/div, 50 V/divPossible Causes
Open circuit on signal wire, spread terminal pin, or short to power feed at Intake Valve Control Solenoid Circuit High (Bank 1)
Bank 1 specific:Inspect wiring harness to cylinder bank 1 (firewall/right bank, exposed to exhaust manifold heat).
Chafed or pinched wiring harness along the signal path to Intake Valve Control Solenoid Circuit High (Bank 1)
Internal mechanical wear or carbon deposits inside Intake Valve Control Solenoid Circuit High (Bank 1)
Defective internal output driver or reference circuit in the control module for Intake Valve Control Solenoid Circuit High (Bank 1)
Symptoms
4
Recommended Solution
Cross-swap the component on Bank 1 with Bank 2 to rule out mechanical oil passages and internal timing wear.
Measure signal terminal voltage with ignition ON and sensor unplugged to determine if ECM pull-up is active or harness is shorted to 12V.
Verify loaded supply voltage and harness terminal pins at Intake Valve Control Solenoid Circuit High (Bank 1).
Check circuit continuity and ground-side voltage drop (< 0.05 V) for Intake Valve Control Solenoid Circuit High (Bank 1).
Command device via scan-tool bidirectional control to verify mechanical operation and flyback spike.
Mechanic's Tip
When an inductive relay/solenoid turns off, an inductive flyback spike (60 - 300 V) MUST appear on the scope. Absence of the spike indicates an open coil winding or an open module driver.