P093C

Code

Generic P — Powertrain

Hydraulic Accumulator Solenoid Circuit High

Brand: Generic

Type: P — Powertrain

Views: UK: 19 EN: 33 RU: 21

AI status

Completed

ready

Completed 100%

Page language: EN

Causes

Short to battery voltage (B+) on the solenoid control wire
Open or high-resistance ground or supply return
Damaged or corroded connector pins or wiring harness
Internal short or failure in the hydraulic accumulator solenoid
Faulty powertrain/PCM module output driver or internal circuit fault
Incorrect or intermittent supply voltage to the solenoid (load dump, charging system issues)

Symptoms

Malfunction indicator lamp (MIL) or fault lamp illuminated
Related hydraulic system warning, reduced hydraulic performance or limp mode
Intermittent or complete loss of hydraulic accumulator or system function
Noisy or unusual behavior from hydraulic pump/actuator when commanded
Possible inability to start/operate depending on system design

What to check

Read freeze frame and stored data with a scan tool; note conditions when code set
Clear code and attempt to reproduce while monitoring live data and outputs
Visual inspection of connectors, pins and harness along route to solenoid and module
Backprobe solenoid control connector and module connector while commanding solenoid ON/OFF
Measure coil resistance (solenoid disconnected) and compare to specification
Check for short to battery: measure voltage at control wire with key ON and engine OFF and with solenoid disconnected

Signal parameters

Typical solenoid coil resistance (nominal): roughly 5–40 ohms (manufacturer-specific — consult service data)
With solenoid disconnected and key ON, control/output pin should not be a steady high (> ~0.5 V) when commanded OFF; unexpected near-battery voltage (~12 V) indicates a short to B+
When commanded ON, expect a PWM-style signal in many systems: amplitude 0–battery voltage, frequency commonly 20–500 Hz (varies by vehicle)
Expected current draw when energized: typically 0.2–2.0 A depending on coil — high current or no current indicates a problem
No excessive voltage spikes or reverse-voltage greater than protective diode rating when measured with scope

Diagnostic algorithm

Retrieve DTCs and freeze frame with a scan tool. Note ignition state, engine speed, battery voltage and any related codes.
Inspect connectors/terminals at the hydraulic accumulator solenoid and the control module for corrosion, bent pins, water ingress or damage.
With ignition off, disconnect the solenoid connector and measure coil resistance across the solenoid terminals. Compare to service spec. Replace solenoid if out of range or shorted to chassis/supply.
Check for short to battery: with solenoid disconnected and key ON (engine OFF), measure voltage at the solenoid control wire. If near battery voltage, trace wiring for short to B+ or stuck relay.
Check for short to ground or open: with key off, measure continuity between control wire and module input/output pin; also check continuity to ground where applicable. Wiggle harness while monitoring for intermittent shorts.
Backprobe the control module output while commanding the solenoid ON/OFF via scan tool. Confirm output transitions and voltage levels. Record waveform with scope if available to look for PWM, spikes or unexpected high-level signal.
Check supply and ground circuits feeding the solenoid and control module (fuses, relays, grounds). Repair any poor grounds or supply issues.
If wiring and solenoid test good, consider substituting a known-good solenoid or harness connector. If fault follows module or driver output does not switch correctly despite good wiring and solenoid, suspect module output driver fault.
After repairs, clear codes and perform function/repeat drive cycle to verify code does not return. Document final tests and results.

Likely causes

Connector terminal pushed out, corroded, or pins contacting B+
Wiring chafed and shorting to chassis or a hot circuit
Solenoid coil internally shorted to battery feed
Control module output driver partially failed and sourcing voltage when it should not
Poor or missing ground at module or solenoid return