My wife's GS300 she says is shaking when she drives it. I used my Blue Driver scan tool today and pulled these codes:

----Antilock Brake System Codes Scan Report----

2 Antilock Brake System Trouble Codes:

1. C1223
ABS Control System Malfunction

2. C1241
Low or High Power Supply Voltage

----Gateway Codes Scan Report----

1 Gateway Trouble Codes:

1. B1206
P/W Master SW ECU Communication Stop


Is this going to be big bucks? or if I reset the codes should the problem go away?

thanks!

 

Assuming this is a 2006 GS300

Does the car shake when taking off or only when braking? Is there any difference in brake pedal feel?

I believe these have reliable electronic ABS modules, you can buy them used at a junkyard for fairly cheap. Maybe less then $100 and pretty sure it doesnt take much time to swap out. But I would do the easy things first and clean the battery terminals and then clean the abs module terminals.

www.car-parts.com is a search engine for local salvage yards

 

Yes, it's a 2006 GS300.

My wife just texted me this (she's the driver):

• Brake pedal feels hard to press on when I start the car first thing in the morning and too loose after I drive it for a while
• Shook randomly yesterday when I was waiting at the red light
• Sometimes feels as if I’m having trouble keeping it driving straight
• General feeling of wobbliness

 

Sounds like to me the brake booster is bad. Brake booster gives the brake pedal more energy when you brake and it is powered by the engine vacuum. Here is a way to test it! Pop the hood open and on the driver side access the brake booster it is the black round cylinder attached to the firewall. There should be 1 large vacuum line, with your fingers pull out that vacuum line. Start the car and you should have lots of vacuum coming from the end of the vacuum line that the engine is creating. Next put your hand on that vacuum line end to block it off, you want to try to hear for any whistling leaking sound. If there isnt then plug it back in, if there is then thats your problem.

Once you reattach the vacuum line, start the engine again and this time while sitting in the driver seat with the engine on, press on the brake. You want see if you can hear air gushing sound. If you here that then the booster itself is bad.

 

I followed your recommendations. The vacuum behaved appropriately. I decided to detach the wiring block and clean the contacts with electronic parts cleaner. A buddy of mine also told me the symptoms my wife reported could have been bad gas or water in the gas (the temperature where we are is all over the map lately, warm and cold in the same day sometimes), so I tossed a bottle of fuel system cleaner into the tank. I drove the car and it was very smooth and responsive.

The ODB tool ran another check and found nothing related to ABS. Pretty weird! but glad not to have to mess with this anymore right now.

Thanks for your insights!

 

How many miles are on this car?

From this code 2. C1241
Low or High Power Supply Voltage

Could be your alternator is going bad and affecting other power related stuff like ABS steering etc. Take the car to an auto parts store many can test the alternator to see if the power is weak or not

 

Only 122k. That's a good idea.