Aston Martin diagnostic trouble code
P1488: Exhaust (muffler) Bypass Control Circuit
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
- Electrical and control modules
- Manual coverage
- V8 Vantage, DB9
- Warning-lamp status
- V8 Vantage: Not stated; DB9: MIL
What Aston Martin code P1488 means
Exhaust (muffler) Bypass Control Circuit
DB9 preliminary diagnostic manual · section 2-232
Manufacturer fault-analysis procedure
Manual fault definition
P1488 - Exhaust Muffler Bypass Control Circuit.
Cautions and notes
CAUTION: This code is generated only in the Primary Powertrain Control Module (PCM). Check
that you are working on the correct PCM.
that you are working on the correct PCM.
Test sequence and decision path
1. Connect the WDS and confirm that a P1488 code
is logged in the primary PCM.
2. Raise the vehicle on a hoist. Ensure that the gearbox is in neutral.
3. Have a colleague observe the bypass valves. Start
the engine and ‘blip’ the throttle. Check if the
bypass valves actuate.
If either valve does not actuate, go to step 4.
If the valves actuate, the problem is not present at
this time and testing is complete.
4. Check for +12 volts at boot fusebox Fuse 22 with
the ignition switched on.
If +12 volts is present, go to step 5.
If +12 volts is not present, service the 12 volt
supply circuit to the exhaust bypass system (Boot
fusebox relay 3 and F22). Clear the P1488 code
and run a KOER test to ensure that the problem is
resolved.
5. Switch off the ignition and start the engine.
Access the bypass valves. Have a colleague ‘blip’
the throttle and check if the valves actuate as the
throttle is opened.
If either valve does not actuate, check continuity
of the bypass valve circuit.
If continuity is good, replace the bypass valve.
Clear the P1488 code and run a KOER test to
ensure that the problem is resolved.
If there is a continuity fault, service the circuit as
necessary. Clear the P1488 code and run a KOER
test to ensure that the problem is resolved.
Open the corresponding manual page for wiring diagrams and figures
is logged in the primary PCM.
2. Raise the vehicle on a hoist. Ensure that the gearbox is in neutral.
3. Have a colleague observe the bypass valves. Start
the engine and ‘blip’ the throttle. Check if the
bypass valves actuate.
If either valve does not actuate, go to step 4.
If the valves actuate, the problem is not present at
this time and testing is complete.
4. Check for +12 volts at boot fusebox Fuse 22 with
the ignition switched on.
If +12 volts is present, go to step 5.
If +12 volts is not present, service the 12 volt
supply circuit to the exhaust bypass system (Boot
fusebox relay 3 and F22). Clear the P1488 code
and run a KOER test to ensure that the problem is
resolved.
5. Switch off the ignition and start the engine.
Access the bypass valves. Have a colleague ‘blip’
the throttle and check if the valves actuate as the
throttle is opened.
If either valve does not actuate, check continuity
of the bypass valve circuit.
If continuity is good, replace the bypass valve.
Clear the P1488 code and run a KOER test to
ensure that the problem is resolved.
If there is a continuity fault, service the circuit as
necessary. Clear the P1488 code and run a KOER
test to ensure that the problem is resolved.