Back to 2002 BMW 525i
Help
2002 BMW 525I
2.5L I6 M54•RWD•AUTOMATIC•gas•M54B25
4 active safety recalls on this vehicle — view recalls
Founding sponsor spot is openYour name on every procedure for this vehicle, permanently.Sponsor — $99 →
Repairs0Labor497Torque2182Fluid8DTC1267Battery1Maintenance0Recalls4
P1525high severityPowertrain

Variable Valve Timing Actuator Supply Voltage

on 2002 BMW 525i 2.5L I6 M54 · RWD

What this code means

The DME detected that the supply voltage to the VANOS actuator system is out of specification. Proper voltage is critical for the precise electro-hydraulic control of variable valve timing.

Symptoms

  • Check Engine Light
  • VANOS not operating correctly
  • Power loss at various RPMs
  • Rough idle
  • Poor throttle response

Common causes

  • Low battery voltage
  • Corroded wiring or connectors in VANOS circuit
  • Faulty VANOS solenoid coil
  • DME power supply issue
  • High resistance in power feed

Diagnostic steps

  1. Test battery voltage and alternator output
  2. Measure voltage at VANOS solenoid connector
  3. Inspect wiring for corrosion or damage
  4. Test VANOS solenoid coil resistance
  5. Check DME power supply circuits

Repair notes

Repair the voltage supply issue to the VANOS actuator system.

🔌 Don't have a code reader?
Any of these will read and clear this code — pick by how deep you want to go.
Budget handheld~$40
ANCEL AD410 →
No-phone-needed handheld — reads, clears, live data, freeze frame.
✓ ANCEL official store
Serious DIY~$100
BlueDriver Pro →
Enhanced codes (ABS, airbag, TPMS) plus repair reports.
SHOP FAVORITE
Shop-grade tablet~$300
Autel MaxiCOM MK808S →
Bidirectional tests, service resets, all systems.
✓ Autel official store
Pro diagnostics$1,500+
Autel MaxiSys MS906 Pro →
Full-system pro platform — topology mapping, ECU coding, the works.
✓ Autel official store
As an Amazon Associate and Autel/ANCEL partner, OLP earns from qualifying purchases — how we link. This never changes the specs we publish.

Other Powertrain codes on this vehicle

🔌 Need this data in your app? It's all in the free API →
🔧 Database maintained under the daily editorial review of Chris Hackleman · Master Technician · 20+ years and Jeff Moore · Master Mechanic · 20+ years. Spot an error? Use the Help link above — a human reads every report.
Stuck on this repair? Take it to The Diag Desk — ask a master tech about this exact car → real human answer within 24h, never AI
Share:XRedditFBWhatsAppThreadsEmail
⚠ STILL BEHIND THE PAYWALL
The 2002 BMW 525i repair data is incomplete because no one has sponsored it yet. For $99, we generate the full step-by-step procedures, then fact-check them with a second AI pass and your expert review. Your name on every procedure, permanently.
The same data would cost $169/mo from Mitchell1 or $30/year from ALLDATAdiy — and you'd be renting access, not freeing it. Sponsor once, free forever.
Sponsor the BMW 525i — $99 →
Building an app?
Free API access to all this data — 10 requests/day, no card required.
Get an API key →
Run a shop?
Manage repairs, estimates, and customers with ShopBase — $249/mo, all features included.
Try ShopBase →