OBD Guide

P143B

Reductant Control System Information Signal Message Counter Incorrect

P143B is an OBD-II diagnostic trouble code meaning: Reductant Control System Information Signal Message Counter Incorrect. Common causes: problems with the can bus (open or short circuit), scr control module malfunction. Estimated repair cost: $56–278.

Severity
⚠️ Medium
Can you drive?
Yes, but get it checked soon
Approx. repair cost
$56–278 (est.)

Symptoms

  • Check Engine light comes on
  • Possible engine power limitation
  • Increased consumption of AdBlue reductant
  • SCR system error message on dashboard

Causes

  • Problems with the CAN bus (open or short circuit)
  • SCR control module malfunction
  • Software error in the control unit
  • Damage to the reduction gear system wiring harness
  • SCR Module Power Problems

How to Fix

  1. Check the integrity of the CAN bus and connections
  2. Read decrypted error codes from the SCR module
  3. Check the supply voltage of the SCR module
  4. Update control unit software
  5. If necessary, replace the SCR control module

Related codes

FAQ

What does the P143B code mean?

P143B is an OBD-II diagnostic trouble code that indicates: Reductant Control System Information Signal Message Counter Incorrect

What causes a P143B error code?

The most common causes of P143B include: Problems with the CAN bus (open or short circuit); SCR control module malfunction; Software error in the control unit; Damage to the reduction gear system wiring harness.

How do I fix a P143B diagnostic trouble code?

To fix P143B: Check the integrity of the CAN bus and connections. Read decrypted error codes from the SCR module. Check the supply voltage of the SCR module. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with P143B?

Yes, but get it checked soon

How much does it cost to fix P143B?

The estimated repair cost for P143B is $56–278. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat