I too am new to this stuff, and so far my impression (formerly based just on forum posts from people with the doubtful benefit of OBDII, now reinforced with a very little experience) is that for a lot of people (including quite a few in the trade) a lot of the time, it is a snare and a delusion.

The first code you list is described here

www.obd-codes.com/p0691

(This is just the first site that came up and not necessarily a good one.)

"Cooling Fan 1 Relay Control Circuit Low

The causes and fixes listed assume this is an isolated code, (which yours evidently is not) and that its cause is directly related to the nature of the code, which is very often not the case.

I think your suggestion of an electrical fault is a good one. For example (best case) you might have a loose battery lead, or a bad battery, or (worst case?) your ECM (or whatever its called this week) might be faulty.

If you want to do anything DIY with the codes you'll probably have to search through them online and see if a pattern emerges

Edited by edlithgow on 06/09/2020 at 04:23

The battery could be as old as the car, about 6 years and is now starting to show it's age hence the amount of electrical faults, 15 out of 25 which seems to me to indicate a common electrical fault, and the common throughout so far appears to be the battery. I will have to wait until the diagnostics have been carried out to see what the service station tells me.

The car is now running as it used to. Seat say they had to by trial and error find that two ignition coils had suddenly packed up, causing false codes to be thrown out. Had all 4 coils replaced, and all faults cleared. Myself not sure that the defective coils could give so many fault codes, and not show up a misfire from a cylinder. Any views on this one?

Steve