skohl

Hope someone can help. I have a 2003 gx with 99k and the vsc, vsc off, ABS and brake light come on as well as a buzzer. I have read through the threads and can't find same issues or any with a GX. It does it first thing in the morning for 2-3 miles then stops and then maybe a second or two while driving throughout the day. Brakes operate fine otherwise. I have it in the shop and they got the following codes:

c1223
c1241
c1252
c1256

The mechanic said there doesn't seem to be an issue with master cylinders going bad on the GX but all codes lead it to being bad. Problem is he can't gaurantee that thats the problem and from the research I have done it could be many things from a brake switch to an ABS computer or a Yaw sensor and starting with a $1500 master cylinder repair that might not fix it could get expensive.

Just wondering if anyone else has had this problem.

mann777

What you have is that the ABS with EBD( electronic Brake Distribution & BA( Brake Assist & Trac & VSC system have gone to a fail safe mode. The Buzzer gets activated, because it has detected a fault in the Skid Control, during the VSC operation.
First check the battery, however old or new it is, all faults begin from the battery voltage.
Whatever the mechanic quoted is absolutely bull**** !!!. As the codes which you have mentioned has nothing to do with the Master cylinders.

For the First code 1223 start with Brake Fluid, and check the viscosity or any sludge or slime from the Brake SS line attached to the wheels. If all is ok, then top up whatever is lost from all 4 wheels check. ( Ensure the battery terminal (-) is removed. Do not depress the Brake pedal at this stage, but only while brake bleed do the process for any air removal with the SS lines.

For the Second code - 1241... it is related to battery low voltage, showing signs of death. this is the primary cause for all faults run up shown by you. Secondly go to your Driver Side J/Box and remove the ECU-IG and check with a tester for continuity. if it is good, then replace the battery .Once replaced, you could have the cluster christmas lites dissappear.

For the Third Code - 1252, its related to low volt being supplied by the battery when the key is turned on, the brake booster pumps Pressure switch goes to fail safe mode, Solution - replace the battery.

For the Fourth Code - 1256 relates to the above condition except in this case the pump gets locked, going in fail safe mode and goes under low pressure to the brake booster pumps. Solution - Replace the battery.

Once the battery is replaced you need goto a Autozone and ensure you depress the pedal around 25-30 times to build the brake pressure within all cycliners and ensure bleed the excessive air and connect the connector and fill the brake reservoir to its required level. Clear all codes via the Autozone tool and thats it, Do a test ride on a empty street at 15 mph and tests the braking condition.
Mann