P246B
System
Powertrain (Diesel Emissions)
Scanner required
Full-system scanner (engine, ABS, SRS, transmission, service resets)

Diesel Particulate Filter Restriction — Ash Accumulation

Understand P246B, common causes, and the right SEAFLO pump to diagnose it.

DPF ash load exceeded limit — filter nearing end of service life. Ash cannot be burned off by regen (unlike soot P2463).

Common symptoms

  • DPF warning
  • Frequent regen requests
  • Reduced power
  • May require DPF replacement

Typical causes

  • High-mileage DPF
  • Excessive oil consumption adding ash
  • Wrong engine oil type for diesel
  • Failed regens accelerating ash buildup

What scanner do you need?

Full-system scanner (engine, ABS, SRS, transmission, service resets)

Use live data and freeze frame to confirm the fault before replacing parts. ABS, SRS, and network U-codes usually require a full-system scanner.

Diagnostic tips

  • Record freeze frame data when the code first sets
  • Clear the code only after fixing the root cause
  • Check for related pending codes that point to a common issue
  • Verify battery voltage is above 12.4V before chasing sensor codes

Frequently asked questions

Can I diagnose P246B with a basic code reader?
P246B may set in the engine module, but related diagnostics often benefit from an enhanced or full-system scanner with live data and freeze frame.
Is it safe to drive with P246B?
It depends on the code and symptoms. Flashing check engine lights and misfire codes should be addressed immediately. Consult a professional if unsure.