P243D code meaning
Particulate Filter Regeneration Duration (Bank 2)
Powertrain system Generic code P24xx codes Check engine light
What P243D means
P243D says that a regeneration of the bank 2 particulate filter took longer than the calibrated limit. CARB expects the OBD system to notice when a filter fails to regenerate properly under conditions in which it was designed to. No manufacturer publishes this bank 2 code; the bank 1 version P2458 shows what such a limit looks like, for example on VW's 2014 Touareg TDI, where an accumulated regeneration timer above 93.35 min counts as a fault. Low exhaust temperature on that bank, a weak oxidation catalyst, an incorrect temperature or pressure signal and many short trips all drag the process out. A long regeneration costs fuel and puts extra heat into the filter. P243C covers regenerations that come too often, P243E those that end with soot left in the filter.
P243D at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modeNot expected
- Repair difficultyMedium
- Typical labor0.5 to 3 hours
- Clears after repairAfter a drive cycle
Symptoms of P243D
- Regeneration seems to run for a very long time (fan, idle speed)
- Higher fuel consumption
- MIL on
Common causes of P243D
- Most likelyExhaust on bank 2 not reaching regeneration temperature (short trips, low load)
- PossibleOxidation catalyst on bank 2 converting too little fuel into heat
- PossibleTemperature or pressure sensor giving wrong values
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
DPF b2
What each part of P243D means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| 4 | Area: auxiliary emission controls (catalytic converter, EGR, EVAP). |
| 3D | The exact fault in that area. |
What to do next
- Note P243D and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P243D
What does P243D mean?
P243D means "Particulate Filter Regeneration Duration (Bank 2)". P243D says that a regeneration of the bank 2 particulate filter took longer than the calibrated limit. It is a generic code, so it means the same on every make.
Is it safe to drive with P243D?
Usually yes, for a short time, if the check engine light is steady and the car drives normally. If the light flashes or the car runs badly, stop and have it checked.
Will P243D fail an emissions test?
Yes, it can. P243D is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P243D to fix?
Difficulty: medium. A typical repair takes 0.5 to 3 hours of work. This is a job for a workshop.
Will P243D clear itself after the repair?
After the repair the car has to complete a drive cycle (a mix of city and highway driving) before the test runs again. Until then the readiness monitor shows "not ready", which can fail an inspection.