abs, traction control, E brake and check engine light comes on, code U0121 and U1120 show on scan tool what could be causing it?
I was driving on the express way and out of no where abs, traction control, E brake and check engine light come on the dash board, also the speedometer needle drops to 0 and it would not shift. I shut it off and start it back on and it goes to normal, I drive it for a little bit, and all the lights come back on, the needle drops and It doesn't shift. I scanned it and code U0121 (lost communication with anti-lock brake module) and U1120 (lost wheel distance message) show up. I already checked all abs wheel speed sensor and replaced one, all the lights went off except for check engine light.
Experienced mechanics share their insights in answering this question :
Hi there. The only component that impacts the majority of these systems is a transmission speed sensor. In some cases, the sensor will slowly wear out, lighting individual warning lights when trouble codes are stored in the ECU. However, when all of them illuminate at the same time, it’s likely that the wiring harness was damaged somehow. I would first check the speed sensor and harness to make sure they are not causing your warning light issues first. If this is not the problem, I would recommend having all the OBD-II trouble codes downloaded by a professional mechanic as this might give you a better understanding of the root issue.
How to Identify and Fix Common car Problems ?
Our sources include academic articles, blog posts, and personal essays from experienced mechanics :
If both the ABS and the brake system light come on at the same time, your vehicle is no longer safe to drive. This means there is a serious problem with the car`s braking system and continuing to drive puts yourself and others at risk.
If the brake system is malfunctioning, the traction control light might come on as a result. The light for your ABS might also come on if the brake fluid is low. Your car likely has sensors in those tanks in order to detect when fluids are low, which could be dangerous.
Press the gas pedal 3 times in quick succession. Then, turn your engine on all the way and let it run for a minute. The TCS and ABS lights should reset and go away if there isn`t any underlying problem with your traction control system.
Hello there, the ABS and cruise control systems work together and any fault with the ABS will disable the cruise control. The most likely causes of the ABS light is an issue with the control module, ABS sensor, or low brake fluid.
Examples include the ABS brakes system, the engine diagnostic controls, the emissions systems, among others. All these systems can cause the check engine light to come on. The reason could be a simple harmless issue or a major complicated issue that can be termed as an emergency.
The Check Engine Light Is On
In these cars, the check engine light will turn on if the ABS system is defective. It is often beneficial to learn about your car`s ABS light, check engine light, and other warning lights. Any time these lights turn on, you should address the associated problem right away.
Anti-lock braking system (ABS) malfunction
If the ABS and traction control lights both appear on your Jeep`s instrument panel, you should take your car to the repair shop as soon as possible.
Resetting Your ABS Dashboard Warning Light
Step One: Disconnect the positive cable from your car battery. Then, hold down the brake pedal to drain the vehicle`s electrical system. This will result in a reset of the car`s central computer. Plug the cable back in to restore power.
The ABS light comes on due to anti-lock braking system issues. Causes include low brake fluid, a blown fuse, or abnormal signals from wheel sensors.
One reason your vehicle`s ABS light is on is because it may be sensing abnormally low levels of brake fluid. You`ll be able to notice if your brake fluid is low by the way your car brakes.
Relevant Questions and Answers :
the most relevant questions and answers related to your specific issue
abs, traction control, E brake and check engine light comes on, code U0121 and U1120 show on scan tool what could be causing it?
ANSWER : Hi there. The only component that impacts the majority of these systems is a transmission speed sensor. In some cases, the sensor will slowly wear out, lighting individual warning lights when trouble codes are stored in the ECU. However, when all of them illuminate at the same time, it’s likely that the wiring harness was damaged somehow. I would first check the speed sensor and harness to make sure they are not causing your warning light issues first. If this is not the problem, I would recommend having all the OBD-II trouble codes downloaded by a professional mechanic as this might give you a better understanding of the root issue.
on starting engine light & throttle control and traction control light comes on and car idols hard no codes when scanned
ANSWER : Hello, and thank you for writing in. Unfortunately the first technician is correct in that this can be cause by a wide variety of issues. Considering that it is intermittent, we can assume that there is either an electrical issue (sensor or bad connection), or that there is a particular part which is dirty or failing. There are a couple of ways you can approach this. One being that you attempt to clean, repair, and replace the many number of components that can cause this. A second being that you attempt to replicate the issue by unplugging sensors and trying various tests to try and narrow down what system is being effected. When dealing with a misfiring situation, you need to look into the air intake, ignition (spark), and the fuel systems first. One last consideration is to have the vehicle scanned by another type of code reader. They vary in brand, manufacture compatibility, and software. For more diagnostic help, contact our service department to schedule an appointment, or to obtain a quote once the issue is diagnosed.
Abs light, emergency brake light, steering wheel assist light, engine light, EPC light, traction control light
ANSWER : Hello, thank you for writing in. The vehicle does utilize a lot of the same sensors for these systems. Are there any other codes that are coming up when this code appears? If so you will want to take these into consideration when processing the repair and making a diagnosis. The module may be bad, and replacing it should fix the problem. The lights should turn off once the main computer recognizes the new module and the sensors sync up. If you believe the sensors need to be cleaned you may do so. Do as minimal as possible to make sure you are not damaging the sensor or disrupting the wiring inside. A bad connection would make the lights stay on. With so many lights that are effected by the module being illuminated, the module is likely bad or does not have a connection. Check the connection first and then resort to replacing the unit. For more help with these electrical tests, contact our service department.
While driving on freeway truck goes into a limp mode, and the check engine light, abs light, parking break light, service brake
ANSWER : It is possible that you could be having an issue with your powertrain control module. This is somewhat of a common problem on many GM vehicles. I would recommend having your vehicle inspected by the dealership to determine if the powertrain control module is functioning properly. If not, a reflash of the powertrain control module may resolve the issue but often times it must be replaced.
Traction light/reduced engine power and check engine light coming on
ANSWER : Hello. From what you describe, it would appear that your vehicle may be experiencing some sort of intermittent wiring or sensor issue. If the problem occurred again after driving over a bump, then it may be possible that a damaged or loose wire is shorting or having contact issues. A common issue that can cause stalling is a faulty crank position sensor or wiring. I would carefully examine the engine for any loose or damaged wires. If the Check Engine Light comes back on, I would recommend having the trouble codes scanned before resetting the computer.
Getting 2 then 4 abs codes, brake shutters, speedo dies and engine slowes when Brake and absolutely lights come on,
ANSWER : You definitely want to start by inspecting the front and rear wheel speed sensors; a failure in these circuits will result in several other problems. Begin by connecting a scanner to see if the Powertrain Control Module (PCM) is registering the sensors accurately. With the scanner, you should be able to monitor all the wheel speed sensors while driving. Keep in mind, the rear wheel speed sensor is mounted on the transmission and is the sensor that runs your speedometer.
Once you determine which sensor is not registering, visually inspect the wiring harnesses and, if everything looks good, replace the sensor. In most cases, the sensor is the problem. If you suspect a wiring problem that isn’t visually apparent, you will need to do a continuity test from the PCM to the sensor connector.
If you determine that all the speed sensors are good, you should suspect a problem with ABS pump. The C0267 trouble code indicates there is a wiring problem in the harness to the ABS pump. It is possible that this is the main problem. To test this, you should disconnect the connector from the ABS pump and visually inspect the pins on both ends. A continuity test should be performed in this harness as well.
There are more test procedures for this that are a bit involved. If you are interested in digging more into this, you should pick up a factory repair manual, not a Chilton. The factory repair manuals are superior and you definitely want good information to make a correct diagnosis of your car.
If you need help with this, I recommend an "ABS light is on" inspection.
Good luck!
EPC light on 2004 Jetta. Code said brake switch faulty, but brakes lights worked. Replaced brake switch, now no brake lights.
ANSWER : Hi there. The first thing that pops in my mind beyond of what you have listed is perhaps the electrical harness attached to the brake switch. Perhaps the harness itself is damaged or you have an exposed wire, loose ground wire somewhere. You might want to have a professional mobile mechanic come to your location and complete a brake lights not working inspection to help you diagnose this issue.
When I put my foot on the brake my back left brake light goes off, when I take it off the brake the brake light comes on
ANSWER : I would suggest trying to disconnect and reconnect the wiring to the rear lights. I have seen these older Toyota vehicles rear lighting short out on the lights themselves due to the way the light circuit was made on the lamp housing. Look at the housing circuit on the light to see if one is touching another, and that could tell you why it is malfunctioning. There could also be a problem with the brake light switch. If you are not comfortable dealing with wires, I recommend getting in touch with a certified mechanic who can look at your brake light issue for you to see what’s going on.
