SwedeSpeed - Volvo Performance Forum banner

1 - 2 of 2 Posts

357 Posts
Discussion Starter · #1 ·
For what I have been able to find it seems like these codes relate to an O2 sensor.

Anyone know what I should check or fix to resolve them?

I have a 2006 s40 t5
ATP intercooler, 3inch DP, IPD/MTE stage 2 tune since 3/2010, KN intake

Its been running rough lately so I put it back to stock tune today to see if it runs better.

thanks in advance for the help.

4,372 Posts
Check your codes again. Most of the numbers you supplied don't to jive with anything.

ECM-21CD Long-term fuel trim, idling, bank 1. Lower limit, B5254T3
Diagnostic trouble code (DTC) information ECM-21CD

The engine control module (ECM) receives information from the heated oxygen sensor (HO2S) about the fuel / air mixture. If the fuel / air mixture deviates from λ=1, the short-term fuel trim will compensate for this by adjusting the injection time so that λ=1 is achieved. When the short-term fuel trim makes an adjustment, the integrator median must be adjusted by the long-term trim. The diagnostic trouble code (DTC) will be stored when the long-term trim must be adjusted almost to maximum in the idle range.
The diagnostic trouble code (DTC) can be diagnosed when idling.

Possible source
Leaking injectors
Damaged mass air flow (MAF) sensor
Contaminated engine oil
Oil level too high
Damaged heated oxygen sensor (HO2S).

Close... ???
ECM-E000 Control module communication. Faulty signal, B5254T3
ECM-740C Communication, central electronic module (CEM). Signal too high, B5254T3
Not familiar with any PJB code.
1 - 2 of 2 Posts