Skip the auto shop - Our mechanics make house calls

Q: Locked brakes - 2004 Cadillac CTS

asked by on

Gf said she was driving down the road and car all the sudden. Wouldn't go over 40 mph. Car smelled hot she pulled over. I checked the car out and the calipers were locked on front driver and rear passenger. I though by some freakind chance they went at same time and replaced them. When trying to bleed the calipers they locked again. I'm thinking it is the Ecbm but I'm not sure. Check engine light is on but abs is not. Can't take anywhere to get scanned and to have someone out to scan it will cost about 1/3 of the replacement ecbm. Any advice of what else could cause that issue or if a failing brake module can lock up opposite tires like that?

My car has 170000 miles.
My car has an automatic transmission.

Hi there. From the description you have provided, your vehicle’s left front and right rear caliper locking would have been a combination/proportioning valve before ABS (anti-lock brake system). The EBCM (electronic brake control module) controls the valves in the hydraulic modulator. It could be that the EBCM or hydraulic modulator is at fault.

It could also be stuck brake master cylinder check valve if the modulator is designed for diagonal braking. Braking systems used to be controlled front to rear. The engineers incorporated diagonal braking to balance the braking system. Your vehicle’s Check Engine Light being on should be addressed, although it is unlikely that it is related to the braking system. The ABS computer should be accessed to help determine the cause of the left front and right rear caliper locking-up.

I recommend having your vehicle’s locking brake calipers inspected and repaired by a certified technician, such as one from YourMechanic.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: 2005 Cadillac CTS 3.6L V6. Purchased one week ago and it has a whining noise around 30mph and 1500 to 2000 rpm, but then goes away

The transmission will have different rotating internal parts when is in different gears. If you are getting a whine in lower gears then you have an internal sun gear or thrust bearing going bad inside the transmission. The transmission would...

Q: I was wondering if it would be legal to swap my vq35de motor out of my 350z and replace it with a ls5.3 vortec motor

Check the rules for emissions testing in your locale - they vary widely, especially if you are in a large metropolitan area with "Clean Air" standards and enforcement. California, with its California Air Resources Board, is especially strict. Most regions...

Q: Service Engine Light staying on.

This code is for the oxygen sensor (O2) heater control circuit. O2 sensors in modern vehicles use a heating element to bring the sensor up to operating temperature faster. This allows the powertrain control module (PCM) to use the sensor...

Related articles

How Long Does a Distributor O Ring Last?
The distributor is part of the ignition system in your vehicle and its purpose is to route high voltage from the ignition coil to the spark plug. The spark plug then...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...