Aston Martin diagnostic trouble code
P1550: Power Steering Pressure Sensor Out Of Self Test Range
Use this reference to understand the recorded condition, confirm the available V8 Vantage or DB9 manual coverage, and follow the documented diagnostic checks before replacing parts.
- Code family
- Powertrain
- Vehicle system
- Fuel and air
- Manual coverage
- V8 Vantage, DB9
- Warning-lamp status
- V8 Vantage: Not stated; DB9: MIL
What Aston Martin code P1550 means
Power Steering Pressure Sensor Out Of Self Test Range
DB9 preliminary diagnostic manual · section 2-236
Manufacturer fault-analysis procedure
Manual fault definition
P1550 Power steering pressure sensor out of
self test range. (i.e. Pressure sensor actuated during a KOEO or KOER test).
self test range. (i.e. Pressure sensor actuated during a KOEO or KOER test).
Test sequence and decision path
1. Connect the WDS and confirm that P1550 is
logged. Clear the logged code.
2. Perform a KOEO test, do not move the steering
wheel. Check if P1550 is logged again.
If not go to step 3.
If so, the power steering switch is permanently
actuated or the signal line is short to ground.
Check for short circuits to ground on the signal
line.
If a wiring defect is identified, service the wiring
as necessary and run a KOEO test to ensure that
the problem is resolved.
If no defect is identified, replace the power
steering pressure switch and run a KOEO test to
ensure that the problem is resolved.
3. Perform a KOER test, move the steering wheel
during the test., check that a P1550 code is
logged. If a fault code is not logged, go to step 4.
If a fault code is logged, the system is correctly
detecting changes in power steering pressure. No
fault is present at this time. Testing is complete.
4. Monitor the Power steering switch input to the
primary PCM.
Key on, engine running, turn the steering wheel
in one direction then the other. Check for change
in state of the power steering pressure switch
signal (0.5 - 4.5 volts) during wheel movement.
If the signal correctly indicates wheel movement,
the fault is not present at this time. Treat this as an
intermittent problem.
If the signal does not change state during wheel
movement, replace the power steering pressure
switch and run a KOEO test to ensure that the
problem is resolved.
If the problem recurs, call Aston Martin Technical
Support.
Open the corresponding manual page for wiring diagrams and figures
logged. Clear the logged code.
2. Perform a KOEO test, do not move the steering
wheel. Check if P1550 is logged again.
If not go to step 3.
If so, the power steering switch is permanently
actuated or the signal line is short to ground.
Check for short circuits to ground on the signal
line.
If a wiring defect is identified, service the wiring
as necessary and run a KOEO test to ensure that
the problem is resolved.
If no defect is identified, replace the power
steering pressure switch and run a KOEO test to
ensure that the problem is resolved.
3. Perform a KOER test, move the steering wheel
during the test., check that a P1550 code is
logged. If a fault code is not logged, go to step 4.
If a fault code is logged, the system is correctly
detecting changes in power steering pressure. No
fault is present at this time. Testing is complete.
4. Monitor the Power steering switch input to the
primary PCM.
Key on, engine running, turn the steering wheel
in one direction then the other. Check for change
in state of the power steering pressure switch
signal (0.5 - 4.5 volts) during wheel movement.
If the signal correctly indicates wheel movement,
the fault is not present at this time. Treat this as an
intermittent problem.
If the signal does not change state during wheel
movement, replace the power steering pressure
switch and run a KOEO test to ensure that the
problem is resolved.
If the problem recurs, call Aston Martin Technical
Support.