P0525low severityPowertrain
Cruise Control Servo Control Circuit Range/Performance
on 2009 Audi A8 4.2L V8 · AWD
What this code means
The cruise control servo circuit is reading values outside the expected range. This often means the servo or its wiring isn't responding correctly to commands from the control module.
Symptoms
- Cruise control won't engage
- Erratic speed while cruising
- Check engine light on
Common causes
- Faulty cruise control servo
- Wiring or connector issues
- Bad throttle actuator
- Faulty control module
Diagnostic steps
- Scan for related codes
- Inspect servo wiring and connectors
- Test servo circuit signals
- Verify servo operation with scan tool
🔌 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 FAVORITEShop-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
00532
Supply Voltage B+ Signal too Low
16394
Camshaft/Crankshaft Position Correlation Bank 1
16395
Camshaft Position Actuator Circuit/Open Bank 1
16486
Mass or Volume Air Flow Circuit Low Input
16487
Mass or Volume Air Flow Circuit High Input
16500
Engine Coolant Temperature Circuit Malfunction
16501
Engine Coolant Temperature Circuit Low Input
16502
Engine Coolant Temperature Circuit High Input
16514
O2 Sensor Circuit Bank 1 Sensor 1
16515
O2 Sensor Circuit Low Voltage Bank 1 Sensor 1