If P242F is active, parked regeneration is typically inhibited. The truck thinks your DPF is full of ash, not soot, and the ash isn’t removed through regeneration. The vast majority of the time the system will not allow any active regeneration (parked or rolling) until the differential pressure sensor sees a significant drop in delta pressure across the DPF. If it’s a low mileage truck, it’s often just a bad / false reading from being soot logged from too much idle time or short tripping. The truck needs a heavy work load for a while. Tow something heavy, set cruise at 70-75mph on the highway and let it run at a constant speed under heavy load for about an hour. You’ll get the EGT’s high enough to get good passive regen going. The soot load will drop, the differential pressure sensors will see this, and then it’ll trigger an active regeneration. You’ll get the “automatic exhaust system regeneration in process continue driving” message if it’s going well. If that message pops up you’re on the right track. Keep driving and let the active regen run until it finishes, DPF gauge should go back to 0% when done.
