Replaced the water pump on my '94 SL 500 and after about the 4th or 5th start the CEL came on. Got a code 4 off of pin 4 which as near as I have been able to determine is the AIR pump. It makes sense as in the recheck the vacuum tube to the pump was found to be disconnected. Guess I missed that in the reassembly. Problem is that I have tried several times to cancel the code without success, and the CEL is still on. Any ideas?