Hi, can anyone offer any help with a problem I have with the Adblue/SCR system on my UK 2010 CX7.

ForScan error codes seen include P2047:14-E4, P2047:13-A, P2047:11-EC, P2047:14-AF and U0442:00-AF. Can reset but one of the P2047 and U0442 instantly return.

Car runs in limp mode. Countdown from 520 miles and engine warning light present on dash. Error message re SCR system at startup in centre display.

Error code explanations include :
Code: P2047 - Reductant Injection Valve Circuit / Open (Bank 1 Unit 1)
Additional Fault Symptom: - Circuit Open
Additional Fault Symptom: - Circuit Short To Ground

Local garage says visual inspection of wiring to Reductant Injection Valve/Dosing Unitt reveals no problems.

I've read that you can measure the resistance of the Valve / Dosing Unit to help diagnose.

Can anyone tell me the range of resistances that would be considered ok ?

Or any other advice please ?

Thanks & regards.

 

your car is a 2.2 diesel. you have a problem with your DPF.

Here, this should help you.

https://www.mazdaforum.com/forum/maz...t-codes-40998/

 

Update on solution :

The 'Reductant Injection Valve' was faulty. I asked my local garage to test resistance of the installed valve and it tested short circuit. Also described as 'AdBlue Dosing Module / Urea Injector' I sourced an original Bosch replacement for £220 via ebay (Bosch part : 04440210314 - OEM part nos : R2AX-20-2F0 9A R2AX202F09A 3A6E13250).

For anyone else with similar problems : I measured the resistance of the new replacement valve and found it to be the region of 12 - 13 ohms. My local garage said they had to run a diagnostic procedure on the SCR system with the new valve, before the error codes could be reset. Have driven a few trips since and fingers crossed, it seems fine.