This morning this car would not start. Daughter Catherine rang the RAC, when the man arrived, he opened the bonnet, and immediately spotted the fault - not connected, he said - reconnected it (battery lead presumably) engine then started. The RAC man had a quick look at the horn, but could not see any obvious fault.
She had a local garage change the thermostat recently to extinguish a warning light, I guess they left they battery lead loose.
After their repair Catherine noticed the horn did not work. She is taking the car back to them tomorrow to check the horn. It sounds horribly like the CIM, doesn't it? Browsing Amazon I have found information, and some ebay videos. I read there were recalls. On e-bay new CIMs cost £185 and used ones less. Have any members done it? Some videos change the CIM, others clean the contacts.