No Sound from Indicators or forward sensors.
Horn not working
Secondary Problems were intermitant responses from Steering Wheel Controls.
You may be experiencing other symptons, Airbag Light on, Steering Angle light appearing etc. These may relate to the CIM or elsewhere. However testing some of the following will help isolate the issues.
Dont buy a replacement from EBAY / Scrapyard etc without checking things first or at least
Buying the Keys for the same CIM
Having the Security Code for the Car - Usually in the Service Book on a credit card style slip for the ecu your buying.
Buying the OPcom software - £250 plus a laptop to run it.
Expecting it to work by direct replacement --- IT WON'T
Dont expect to remove the Column Controller ECU and fit a new one without having it programmed to the Car Keys and Engine Controller.
Use Youtube Videos to remove the Steering Column Casing and Steering Wheel and AIR BAG.
Continuity of Connections. The Airbag and Horn connections are done through two connectors on the back of the Airbag unit PINK and PURPLE plugs.
The CIM has a Large Plug around the back to the Left...Unplug this and use a Continuity Meter to test the connection from the PINK and Purple Connectors to the BACK of the CIM unit See PICS below. This will verify the HORN Circuit and AIR Bag Circuit is connected through the CIM Ribbon Cable.
There is a smaller 6 PIN socket next to the PINK and PURPLE connector. This runs the Steering Wheel controls. You can test continuity of these PINS through CIM unit to the Back plate.
All of these connections are run through a RIBBON Cable that often gets damaged see images below for where to spot Damage.
If you find continuity for the HORN and Steering Wheel Controls , then the issues lie elsewhere. Try the Horn relay and fuse or Horn Itself.
Try shorting the Horn Relay socket to sound the horn. Check the connection to the Horn ( Low down Front Driverside behind Valance)
The Steering Wheel Controls are a often damaged due to wear, If your getting intermittant connections for Volume / Screen adjustments etc. These are small plastic units that are wired to the plug on the Steering Wheel. The 8 pin plug runs these through the Ribbon Cable to the back of the CIM.
If your getting Strange issues like Ignition logic on Radio or Volume Control issues or other things happening regards the Central Media and Climate console, then the Steering Wheel controls may be causing intermittent connections. If you dont have Steering Wheel controls then the CIM may well be faulty and needs replacement.
The Ribbon Cable can be damaged from wear and tear and through being wound and unwound. This causes intermitant and high resistance connections to HORN, AIRBAG and Controls.
If the Steering Wheel has been removed the the Hub of the CIM wound too tight to assist in Setting Steering Angle, this can cause the Ribbon cable to be over tightened and snap if the Wheel is turned. Be aware that winding the central bobin tightens this cable, so make sure its not tight before setting the angle markers for centralising the Steering.