Hi Drover, I reset the codes, drove about 100klm, checked and they were back up.

So I cleared the codes, switched the engine off, then back on again but didn't drive and re read the codes, they had returned.

I cleared the codes again but didn't switch off, re read the codes non showing, drove about 60klm re read the codes non showing. Switched off the car and left it for a while, turned the car back on but didn't drive, read the codes and they are back up.

So it would appear the codes are being activated when the car is started, not when it is being driven, as they didn't activate when I cleared them then drove the car and re read them.
So it looks as though they are just stored codes, I will just monitor it.
I'm sure the neighbours think I'm going mad, sitting in the car with the engine running all the time.:lol:

I may be wrong but if the codes were of any worry I think the BCM/ECU or one of those things would throw a yellow engine on the dash..... I only look for codes when something is amiss, otherwise I don't bother but if I knew there were some there they would drive me nuts............

You are spot on, I only looked because it was a 2nd hand unit, but I'm confident, now I've done some checks, all is good.
Thanks for the help.

Mate, its a continual learning curve for all of us, every bit of info helps as these things throw curve balls all the time.......... :cool:

Has anyone had any problems since having this done? I immediately noticed my displayed fuel economy got better by a 1-2 l/100km but now after a long trip I'm getting P0428 (Catalyst Temperature Sensor High) engine error codes. Could it be related? Jeep in Brisbane have 3 week wait before they can look into it. I'm not keen to drive back to Cairns without the error being investigated. I'm starting to worry about how much it will cost to fix.

Have a read of this link as it relates to the eco diesel:

https://www.tsbsearch.com/Jeep/18-012-16

Page 5 para 10 refers to the exhaust gas temperature sender (part # 5146662AB, Walker part# 273-10332, https://www.moparpartsgiant.com/part...5146662ab.html)
which is located at the DPF inlet (which may be related to your P0428 code) & how to clean/test the sensor

This link:
https://www.jeepgarage.org/threads/code-p0428.99648/

also refers to a similar problem & mentions DPF cleaning.

Cheers

If you have just been toottling around town it could be a DPF burn thing, my recall update was about 10,000km ago or more with no dramas, the fuel economy thing often wanders around on mine I sometimes suspect the brand of fuel .