P24F0

Code

Generic P — Powertrain

Control Module Wake-up Circuit Low

Brand: Generic

Type: P — Powertrain

Views: UK: 15 EN: 42 RU: 25

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Page language: EN

Causes

Blown fuse or tripped relay on wake/wiring circuit
Open, short to ground, or high resistance in wake-up wire or connector
Failed or intermittent connector pin contact (corrosion, bent pin)
Faulty wake source (e.g., BCM, body control module, ignition switch, telematics unit)
Control module internal input circuit failure
Low battery/insufficient system voltage or excessive voltage drop

Symptoms

No response from the affected control module on key-on or remote wake events
Vehicle may not perform functions controlled by the module until ignition is cycled or module is forced awake
Extended crank or no crank if a powertrain module fails to wake (depending on module)
One or more communication bus messages missing or modules show as not present on a scan tool
Interior electronics may not behave normally (e.g., locks, windows, remote start failures)

What to check

Connect a factory-level scan tool; confirm P24F0 stored and note freeze-frame data and counts
Check battery resting voltage and cranking voltage (should be ~12.6 V at rest, >9.6 V while cranking)
Verify related fuses and wake relays are intact and seated correctly
Inspect connectors and wiring in the wake signal path for damage, corrosion, bent pins, or water intrusion
Backprobe the wake input at the control module with ignition/key in OFF, ACC, and ON to observe changes
Check chassis and engine grounds for tightness and corrosion

Signal parameters

Wake-line behavior depends on vehicle architecture—consult service manual for exact values
Common wake-line types: 12 V switched wake: inactive ~0 V (or open), active ~9–14 V when request present
Logic-level or control-line wake (5 V logic): inactive ~0–0.5 V, active ~4–5 V
For CAN bus wake: bus idle ~2.5 V (CAN_H ~2.5 V / CAN_L ~2.5 V); wake/traffic shows CAN_H pulses up to ~3.5 V and CAN_L down to ~1.5 V
Use oscilloscope to capture waveform if intermittent: expect a clean transition/pulse when wake is commanded

Diagnostic algorithm

Verify DTC: Clear codes, cycle ignition and attempt to reproduce; confirm P24F0 returns and capture freeze-frame.
Battery and power: Measure battery resting voltage and check for excessive voltage drop during crank or wake attempts. Recharge/replace battery if weak.
Fuses/relays: Locate and inspect fuses and relays for the module's wake circuit; replace if faulty.
Visual inspection: Inspect wiring and connectors for the wake input path from the wake-source (ignition switch, BCM, telematics unit) to the affected module. Repair visible damage.
Backprobe and measure: With a digital multimeter or oscilloscope, backprobe the module wake input connector while commanding a wake (key ON, remote request). Confirm expected voltage or waveform per service manual.
Verify grounds: Check resistance from module ground pins to battery negative; clean/tighten ground connections as required.
Isolate loads: Disconnect aftermarket devices or non-essential modules that may hold the line low. Re-test.
Check upstream module: If the wake signal originates from another control module (BCM/IPC), verify that source module wakes and drives the wake line correctly. Scan for related communication or wake-source faults.
Wiring continuity: If signal is low, disconnect both ends and check continuity and resistance of the wake conductor; repair open/high resistance or short-to-ground.
Reprogram/replace: If wiring and upstream sources are good and signal never reaches the module, consider replacing the module input connector or the module itself only after confirming fault is not harness-related. Reprogram or update module software per manufacturer instructions.
Final verification: Clear codes, perform full wake-cycle tests (remote, key, automatic wake scenarios) and confirm normal operation and no reoccurrence of P24F0.

Likely causes

Blown fuse or faulty wake relay for the module
Open or damaged wake-up wire between wake-source module and affected control module
Faulty connector (corroded pins or poor crimp) at the control module
Dead/weak battery or poor ground causing voltage drop on wake line