Aston Martin diagnostic trouble code
P1235: Fuel Pump Driver Module Range or perfomance
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 P1235 means
Fuel Pump Driver Module Range or perfomance
DB9 preliminary diagnostic manual · section 2-218
Manufacturer fault-analysis procedure
Cautions and notes
NOTE: On the circuit diagrams, MPF is the pulse width
modulated signal which drives the fuel pumps. FPM is
the Fuel Pump Monitor diagnostic signal.
modulated signal which drives the fuel pumps. FPM is
the Fuel Pump Monitor diagnostic signal.
Test sequence and decision path
1. Connect the WDS and confirm that either P1233/
35 or 1237 is logged. Note and clear all logged
codes.
2. Swap the FPDM connectors side to side. Run a
KOER test. Check for DTC codes. If the P1233/35
or 1237 fault has swapped to the alternative
PCM, replace the fuel pump drive module.
If the fault has not swapped sides, FPDM is OK go
to step 3.
3. If P1237 is logged, go to step 4. For other FPDM
codes, go to step 5.
4. If code P1237 is logged, disconnect the FPDM.
Perform a continuity check across the fuel pump.
The pump motor resistance should be approximately 4
Ω
. If the resistance reading is significantly different, access the evap loss flange,
disconnect the loom connector and repeat the
pump motor resistance check.
If the resistance is now correct, service the harness wiring as necessary. Reconnect all components. Clear the fault code and run a KOER test to
ensure that the problem is resolved.
If the resistance is still incorrect, replace the fuel
pump. Reconnect all components. Clear the fault
code and run a KOER test to ensure that the problem is resolved.
5. Install the break-out box to the PCMs. Perform
continuity checks on the PCM to FPM lines.
If a circuit fault is detected, service the wiring as
necessary. Reconnect all electrical plugs and run
a KOER test to ensure that the problem is
resolved.
If P1233/35 are still logged, call Aston Martin
Technical Services.
Open the corresponding manual page for wiring diagrams and figures
35 or 1237 is logged. Note and clear all logged
codes.
2. Swap the FPDM connectors side to side. Run a
KOER test. Check for DTC codes. If the P1233/35
or 1237 fault has swapped to the alternative
PCM, replace the fuel pump drive module.
If the fault has not swapped sides, FPDM is OK go
to step 3.
3. If P1237 is logged, go to step 4. For other FPDM
codes, go to step 5.
4. If code P1237 is logged, disconnect the FPDM.
Perform a continuity check across the fuel pump.
The pump motor resistance should be approximately 4
Ω
. If the resistance reading is significantly different, access the evap loss flange,
disconnect the loom connector and repeat the
pump motor resistance check.
If the resistance is now correct, service the harness wiring as necessary. Reconnect all components. Clear the fault code and run a KOER test to
ensure that the problem is resolved.
If the resistance is still incorrect, replace the fuel
pump. Reconnect all components. Clear the fault
code and run a KOER test to ensure that the problem is resolved.
5. Install the break-out box to the PCMs. Perform
continuity checks on the PCM to FPM lines.
If a circuit fault is detected, service the wiring as
necessary. Reconnect all electrical plugs and run
a KOER test to ensure that the problem is
resolved.
If P1233/35 are still logged, call Aston Martin
Technical Services.
Supporting owner context
What owners have reported
Owner cases underline that fuel-pump-driver codes can involve communication, power, earth, wiring or the driver module itself. Follow the manufacturer sequence before replacing the pump or driver module.
This is supporting owner-reported context, not a replacement for the manufacturer procedure or a diagnosis of every vehicle.
Read the related owner discussion