Aston Martin diagnostic trouble code
P0108: Manifold Absolute Pressure/BARO Sensor High Input
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: MIL; DB9: MIL
What Aston Martin code P0108 means
Manifold Absolute Pressure/BARO Sensor High Input
DB9 preliminary diagnostic manual · section 2-18
Manufacturer fault-analysis procedure
Manual fault definition
P0108 - The barometric pressure signal went high
during normal engine running.
during normal engine running.
Cautions and notes
CAUTION: The barometric pressure signal is
input only into the Primary PCM.
CAUTION: The barometric pressure signal is
input only into the Primary PCM. Check that you
are working on the correct half of the engine.
input only into the Primary PCM.
CAUTION: The barometric pressure signal is
input only into the Primary PCM. Check that you
are working on the correct half of the engine.
Test sequence and decision path
1. Connect the WDS or Scan Tool. Check that fault
code P0108 is present.
2. Using WDS, monitor the BAP signal. If the signal
level is not within the range 2.45 - 4.8 volts, go to
step 3. If the signal level is within the range 2.4 -
4.8 volts, the fault is not currently present. Treat
this as a possible intermittent problem.
3. Switch off the ignition. Disconnect C0188 at the
barometric pressure sensor. Connect a voltmeter
across pins 1 and 2 of the harness connector.
Switch on the ignition.
If +5 volts is measured, the BVREF and Signal
return lines are good. go to step 4.
If +5 volts is not present, troubleshoot the +5 volt
supply and signal return lines from the primary
PCM.
4. With the meter connected to pins 1 and 2 of the
barometric pressure sensor and the ignition
switched on, shake/wiggle the harnesses between
the sensor and the PCM to detect any short circuit
from +12 volts to the BAP signal or return lines. If
the meter reads more than +4.8 volts at any time,
go to step 5.
If the signal remains in the range 0-4.8 volts, the
problem cause is not present at this time and testing is complete.
5. Check and service the short circuit from +12 volts
to the BAP signal line. Clear the P0108 code. Run
a KOER test to ensure that the problem is
resolved.
P0109 - Barometric Pressure Sensor
Figure 1. Barometric Pressure Sensor Location
Figure 2. BFS - PCM Interface Circuit
Boot (Trunk) Fusebox
Barometric Pressure Sensor
Y,0.5
BP,0.5
P,0.5
BP,0.5
Y,0.5
P,0.5
BP,0.5
Y,0.5
P,0.5
C0117-20
C0117-19
C0117-18
Sensor-Barometric Pressure
C2243-17
C2243-18
C2243-16
Primary PCM
C0188-2BVREF
C0188-1SIGRTN
C0188-3BAP
SPL26-BVREF/EN
SPL11-SRTN/EN
C0634-40G BVREF
C0634-41G
SIGRTN
C0634-36G BAP
Fault Code Definition
P0109 - The barometric pressure signal was intermittent.
MIL Status
This code will not light the MIL lamp
P0109 Fault Analysis
1. Connect the WDS or Scan Tool. Check that fault
code P0109 is present.
2. Using WDS, monitor the BAP signal. If the signal
level is not within the range 2.45 - 4.8 volts, go to
step 3. If the signal level is within the range 2.4 -
4.8 volts, the fault is not currently present.
3. Switch off the ignition. Disconnect C0188 at the
barometric pressure sensor. Connect a voltmeter
across pins 1 and 2 of the harness connector.
Switch on the ignition.
If +5 volts is measured, the BVREF and Signal
return lines are good. go to step 4.
If +5 volts is not present, troubleshoot the +5 volt
supply and signal return lines from the primary
PCM.
4. With the meter connected to pins 1 and 2 of the
barometric pressure sensor and the ignition
switched on, shake/wiggle the harnesses between
the sensor and the PCM to detect any short circuit
from +12 volts to the BAP signal or return lines. If
the meter reads more than +4.8 volts at any time,
go to step 5.
If the signal remains in the range 0-4.8 volts, the
problem cause is not present at this time and testing is complete.
5. Check and service the short circuit from +12 volts
to the BAP signal line. Clear the P0109 code. Run
a KOER test to ensure that the problem is
resolved.
Open the corresponding manual page for wiring diagrams and figures
code P0108 is present.
2. Using WDS, monitor the BAP signal. If the signal
level is not within the range 2.45 - 4.8 volts, go to
step 3. If the signal level is within the range 2.4 -
4.8 volts, the fault is not currently present. Treat
this as a possible intermittent problem.
3. Switch off the ignition. Disconnect C0188 at the
barometric pressure sensor. Connect a voltmeter
across pins 1 and 2 of the harness connector.
Switch on the ignition.
If +5 volts is measured, the BVREF and Signal
return lines are good. go to step 4.
If +5 volts is not present, troubleshoot the +5 volt
supply and signal return lines from the primary
PCM.
4. With the meter connected to pins 1 and 2 of the
barometric pressure sensor and the ignition
switched on, shake/wiggle the harnesses between
the sensor and the PCM to detect any short circuit
from +12 volts to the BAP signal or return lines. If
the meter reads more than +4.8 volts at any time,
go to step 5.
If the signal remains in the range 0-4.8 volts, the
problem cause is not present at this time and testing is complete.
5. Check and service the short circuit from +12 volts
to the BAP signal line. Clear the P0108 code. Run
a KOER test to ensure that the problem is
resolved.
P0109 - Barometric Pressure Sensor
Figure 1. Barometric Pressure Sensor Location
Figure 2. BFS - PCM Interface Circuit
Boot (Trunk) Fusebox
Barometric Pressure Sensor
Y,0.5
BP,0.5
P,0.5
BP,0.5
Y,0.5
P,0.5
BP,0.5
Y,0.5
P,0.5
C0117-20
C0117-19
C0117-18
Sensor-Barometric Pressure
C2243-17
C2243-18
C2243-16
Primary PCM
C0188-2BVREF
C0188-1SIGRTN
C0188-3BAP
SPL26-BVREF/EN
SPL11-SRTN/EN
C0634-40G BVREF
C0634-41G
SIGRTN
C0634-36G BAP
Fault Code Definition
P0109 - The barometric pressure signal was intermittent.
MIL Status
This code will not light the MIL lamp
P0109 Fault Analysis
1. Connect the WDS or Scan Tool. Check that fault
code P0109 is present.
2. Using WDS, monitor the BAP signal. If the signal
level is not within the range 2.45 - 4.8 volts, go to
step 3. If the signal level is within the range 2.4 -
4.8 volts, the fault is not currently present.
3. Switch off the ignition. Disconnect C0188 at the
barometric pressure sensor. Connect a voltmeter
across pins 1 and 2 of the harness connector.
Switch on the ignition.
If +5 volts is measured, the BVREF and Signal
return lines are good. go to step 4.
If +5 volts is not present, troubleshoot the +5 volt
supply and signal return lines from the primary
PCM.
4. With the meter connected to pins 1 and 2 of the
barometric pressure sensor and the ignition
switched on, shake/wiggle the harnesses between
the sensor and the PCM to detect any short circuit
from +12 volts to the BAP signal or return lines. If
the meter reads more than +4.8 volts at any time,
go to step 5.
If the signal remains in the range 0-4.8 volts, the
problem cause is not present at this time and testing is complete.
5. Check and service the short circuit from +12 volts
to the BAP signal line. Clear the P0109 code. Run
a KOER test to ensure that the problem is
resolved.