What does this code mean?
Race Director
Joined: May 2005
Posts: 15,960
Likes: 21
From: West Norriton PA
St. Jude Donor '08
Burning Brakes
Joined: Jan 2006
Posts: 1,170
Likes: 27
From: Magnolia Greens NC
try this cure from another member..
Service ABS/Service Traction Control DTC C1243 H
I have had this problem with my 98 C5 now for going on 6 months. I have worked on it on and off as my electronics service job permits since I travel for work. I followed the advise on the forum about checking and cleaning the ground connections as well as other suggestions. Nothing seemed to make a difference until I ran across the thread about a member who was clearing the code while driving and then slamming on the brakes to activate the ABS. I know when the car is started the system turns the ABS pump on and off and if the voltage read back is not high enough the code C 1243 is set and you get the messages. Since I do not have the interface connector for the EBCM I pulled the module away from the pump section. I measured the resistance of the pump motor from pin number 8 ((from left to right) (it is the first pin on the right hand connector))to the frame ground and it was in spec according to the manual. In my job we also use different size pumps for pressure and vaccuum. When a pump is new or has been rebuilt it requires some break in period. If a pump has been used and off for some period of time it will also draw more current due to sediment build up and not being exercised. With this in mind I pushed a wire into pin 8 and ran it over close to the positive post of the battery so I could exercise the pump manually. The pump came on the first time I touched the positive post but sounded sluggish. I exercised the pump about 6 more times for about 15 to 20 seconds at a time. I put the EBCM back on the pump section cleared the codes and so far the car has been running for one week now with only one message the first day after this procedure that message cleared on the next start by itself. If you try this use a heavy gauge wire and be aware the wire may get warm as you touch the battery. The pumps on these ABS units are most likely not broken in since they hardly run during the life of the car. The car has been running fine with no more Traction control codes or Service ABS messages now for three weeks. The car has been running great with no problems now for six weeks.
I have had this problem with my 98 C5 now for going on 6 months. I have worked on it on and off as my electronics service job permits since I travel for work. I followed the advise on the forum about checking and cleaning the ground connections as well as other suggestions. Nothing seemed to make a difference until I ran across the thread about a member who was clearing the code while driving and then slamming on the brakes to activate the ABS. I know when the car is started the system turns the ABS pump on and off and if the voltage read back is not high enough the code C 1243 is set and you get the messages. Since I do not have the interface connector for the EBCM I pulled the module away from the pump section. I measured the resistance of the pump motor from pin number 8 ((from left to right) (it is the first pin on the right hand connector))to the frame ground and it was in spec according to the manual. In my job we also use different size pumps for pressure and vaccuum. When a pump is new or has been rebuilt it requires some break in period. If a pump has been used and off for some period of time it will also draw more current due to sediment build up and not being exercised. With this in mind I pushed a wire into pin 8 and ran it over close to the positive post of the battery so I could exercise the pump manually. The pump came on the first time I touched the positive post but sounded sluggish. I exercised the pump about 6 more times for about 15 to 20 seconds at a time. I put the EBCM back on the pump section cleared the codes and so far the car has been running for one week now with only one message the first day after this procedure that message cleared on the next start by itself. If you try this use a heavy gauge wire and be aware the wire may get warm as you touch the battery. The pumps on these ABS units are most likely not broken in since they hardly run during the life of the car. The car has been running fine with no more Traction control codes or Service ABS messages now for three weeks. The car has been running great with no problems now for six weeks.
