2 like 0 dislike
12.3k views
by

I have a 2013 Isuzu NPR HD 5.2L I4 with engine codes P1490 & P20C9, fuel condition good, fluid levels correct

Vehicle: 2013 Isuzu NPR HD 5.2L I4

2 Answers

1 like 0 dislike
by (13.4k points)
 
Best answer
P1490 Diesel exhaust fluid (DEF) system Nox trap low effieicncy

P20C9 Diesel exhaust fluid (DEF) control moduel request Mil light on

The DEF is not discolored ? and there no sign of DEF injector leakage? If all okay you need to reprogram the DCU , Isuzu had this problem with this code condition and produced a TSB for it # SB13-L-001B , it falls under a warranty where they will reset the calibration
0 like 0 dislike
by (8.3k points)
  • Check Diesel Exhaust Fluid (DEF) level and condition
  • Faulty Nitrogen Oxide (NOX) Sensor(s)
  • Faulty Reductant Control Module
  • Reductant Control Module harness is open or shorted
  • Reductant Control Module circuit poor electrical connection

P20C9 Isuzu Code - Diesel Exhaust Fluid Control Module Requested MIL Illumination
Read more: https://www.autocodes.com/p20c9_isuzu.html

Related questions

1 like 0 dislike
1 answer 3.7k views
1 like 0 dislike
1 answer 793 views
1 like 0 dislike
1 answer 671 views
1 like 0 dislike
1 answer 981 views
1 like 0 dislike
1 answer 442 views

36.2k questions

32.2k answers

1.3k comments

22.8k users

Need A Repair Shop?
Find local automotive repair shops in your area.
Does your car have Safety Recalls? → Check here
...