What car does she have ?
Fit the blank & drive the car & see what happens.
Any OBD II reader off ebay should be fine ( £15 approx. )
The car is a 2007 1.6 TDCI Estate,I fitted blanking plate and returned car to daughter. It seemed to run well, fault still shows on OBD and no engine failure light on dash, but that had disappeared anyway before fitting plate. Will see what happens in next few weeks.
Fitting dd not go well, here are some notes which may help others,
1. I managed to crack the windscreen when removing the top cover strip under the wipers. HOW? With all clips removed it just would not come away from one particular point under the windscreen, so extra force (not a lot) was used resulting in crack. On examination it appears some excessive mastic from under the windscreen had come out and stuck the cover plate to the screen. Even knowing this now, I am not sure there is anything I could have done different, insurance excess £75.
2. Fixing nut holding EGR cooler was very difficult to access and immpossible to see. A 10mm socket appeared to fit but when engaged with 1/4" adapter it keep slipping off, after some thought I realised the thread length was very long and interferred with end of adaptor in socket prevented proper engagement. Had to only slightly engage adaptor to give room for thread length and allow socket to fully engage on nut.
3. Blanking plate not symmetrical, you need to study manifold shape to determine direction of fitting, not easy as difficult to see. To aid visual access I lifted out the fuel filter (while still connected)
4. When finally fitted and clamped up I noticed some gasket 'hanging' out from the joint. Not happy and wondered if gasket wrongly fitted. I unclamped the joint, removed the plate, removed both clamping screws and moved the EGR valve away as far as possible to inspect the gasket. All was well, the gasket fully covered the mating faces and was oversize at one point, producing the overhang.
As you can see, I did not find this job particularly easy or cheap, maybe I am useless or maybe a bit unlucky.
Still unsure about these OBD devices, I read about some that will do some very fancy stuff, while mine does not even seem able to delete a basic fault code. Need to do more research.