I have a 1998 C5 that has an issue with the TCS troublecode C1241 (Magnasteer Failed). The other day I was driving normally and was applying the brakes (not hard) and heard/felt something weird and the ABS/TCS/Service Vehicle Soon message popped up. I found the #5 Fuse (ABSTRANS) was blown. So, I replaced that and that took care of the ABS/TCS/Service Vehicle Soon message. But there was still a C1241 code for Magnasteer circuit issue. This will not clear. I read some of the diagnostic procedures. I checked the actuator connector for the VES coil that runs through the rack and controls the Magnasteer. The connector was undamaged and pins were fine. I checked the resistance which the range is 1.6-3.1 ohms and I have 2.5 or so. I did check with it plugged in just to see if there was a difference and backprobbed it. it then jumped to 3.1/3.2 ohms. Anyways, it did pass the tech manual checked when unplugged and I did check for shorts to ground and voltage with none found. So, I checked for continuity between the EBCM plug and the Magnasteer connector and didn't have any opens there. I then checked voltage at the Magnasteer connector with key on and had about .5v which I think(?) is okay according to what I can tell from the flow chart. I did check for battery voltage at the EBCM and had that as well. So, I borrowed a Snap-on scanner to try to read the Magnasteer data. Apparently this codes is set when the difference between the Magnasteer Commanded Current has a 0.05 amps or more difference than the Magnasteer Feedback Current. Proper range is between -2amp and 0mph or +3amps above 45 mph. The scanner read a proper Magnasteer Commanded Current of -1.74amps which is correct, but the Magnasteer Feedback Current stays at 0amps the entire time at any speed. That is the issue. So what controls the Magnasteer Feedback Current? Is that done through the Magnasteer coil in the rack even though the coil resistance checks out when unplugged, or is it controlled by the EBCM. I read the 97/98 EBCM's have an internal relay that controls the Maganasteer cirucuit. So, is it an EBCM issue or steering rack? What controls the Magnasteer Feedback Current? This all started when #5 fuse blew and not sure why it blew or if something internally in EBCM or steering rack spiked was the root cause? Thanks!-Jason

 

Anyone have any input or ideas?