Before I dive into messing with my master cylinder I need to figure out what is causing my ABS issue. Is my soft brakes causing my ABS not to kick in, or is my ABS causing my soft brakes (I dont think this but I really dont know), or is my ABS issue totally separate.
I have no ABS. When I take the car up to 70 and slam on the brakes, it just brakes normally like I'm doing 30. No screeching to a halt, no pulsating, no locking. I don't get an ABS warning light. When I start the car up the light comes on and goes out as normal.
How can I test and fix this issue? I'm looking for a way without needing the Consult III, or needing to test continuity with a VOM because I doubt continuity is my issue.
Thanks.
I have no ABS or light.
Re: I have no ABS or light.
process of elimination - 1) fuse, any fuse related to ABS
2) - scan for codes; somewhat related, test ABS module, here you might need some sort of computer and yes i know you don't have Consult III
3)- go grab another ABS module from junkyard and see what happen.
2) - scan for codes; somewhat related, test ABS module, here you might need some sort of computer and yes i know you don't have Consult III
3)- go grab another ABS module from junkyard and see what happen.
Re: I have no ABS or light.
I would say that your warning lights come on at startup then go off as expected; indicates to me that you have no problem.
It seems like that is a result of soft pedal (phrase that covers a lot of issues). Therefore, troubleshoot the issues you have identified here and in the other thread.
So, do you have new pads, rotors or tires?
Have you checked or serviced the calipers to make sure the brakes are all engaging normally?
This test doesn't have to be an all-out disassembly of the car. [You strike me like the kind of guy that has an infrared thermometer handy, lol. Everyone should, really]
*******************
Just to clarify, the system you are looking for is called Brake Assist. BA uses the pedal sensor to monitor the urgency of the braking request and:
1. Tightens the seat belt
2. Engages the other features to brake earlier and thus shortens the stopping distance.
When you slam the brake, say at 45mph, does the seatbelt tighten?
Antilock Brake System absolutely won't engage unless it thinks a wheel is slipping. Again, ABS is very responsive and the lights will stay on if there's an issue.
Pull fuses as suggested to see what happens. If nothing changes and no lights stay on, then we have a problem.
Otherwise, a good way to test ABS without Consult is to make the drive wheels slip. Find an icy patch or just do it safely at home as follows:
Jack the drive wheels off the ground and secure the car on jackstands. Caution: All four wheels should go up if you have AWD
Does this mean that it takes a very long distance to stop, or do you mean it stops in good distance - just no drama or fanfare?When I take the car up to 70 and slam on the brakes, it just brakes normally like I'm doing 30. No screeching to a halt, no pulsating, no locking
It seems like that is a result of soft pedal (phrase that covers a lot of issues). Therefore, troubleshoot the issues you have identified here and in the other thread.
So, do you have new pads, rotors or tires?
Have you checked or serviced the calipers to make sure the brakes are all engaging normally?
This test doesn't have to be an all-out disassembly of the car. [You strike me like the kind of guy that has an infrared thermometer handy, lol. Everyone should, really]
- After a good straight line run, brake normally and pull into a parking lot etc (a distance that doesn't allow the brakes to cool down).
- Go around the car checking the rotor/hub temperatures
- Aim for the non-reflective parts of the rotor - like the center, and compare numbers.
- You should have approx the same readings on the left and right side.
The front rotors will be approx 20 degrees F hotter. - That varies, but in general front>rear, left=right as pertains to temperature.
- If one of them is too cold or too hot, then progress to the disassembly stage of troubleshooting because that one isn't working well.
*******************
Just to clarify, the system you are looking for is called Brake Assist. BA uses the pedal sensor to monitor the urgency of the braking request and:
1. Tightens the seat belt
2. Engages the other features to brake earlier and thus shortens the stopping distance.
When you slam the brake, say at 45mph, does the seatbelt tighten?
Antilock Brake System absolutely won't engage unless it thinks a wheel is slipping. Again, ABS is very responsive and the lights will stay on if there's an issue.
Pull fuses as suggested to see what happens. If nothing changes and no lights stay on, then we have a problem.
Otherwise, a good way to test ABS without Consult is to make the drive wheels slip. Find an icy patch or just do it safely at home as follows:
Jack the drive wheels off the ground and secure the car on jackstands. Caution: All four wheels should go up if you have AWD
- Start the car and ensure your foot is on the brake
- Shift it into D.
- Release the brake pedal and entertain yourself.
- The brake pedal pulsates
- You hear mechanical noises from the engine bay
- Your engine might stumble or cut out as the SLIP light comes on and off
- You might hear the pads slapping on the drive wheels as the caliper engages.
Re: I have no ABS or light.
How? And yes I am able to check for codes.
Correct
New front, decent rears.
Lmao, I do. So I'll try that.
Yes
Ok, I'll figure out the corresponding fuses.
So once I'm jacked up, take the car above 45 and brake and the ABS should kick in? And this is because there is no resistance since it's in the air which will make the car believe it is slipping?
Re: I have no ABS or light.
From your responses, it seems the car is fine. The new brakes are doing a fine job bringing you to a regulated stop.
The pads are grabbing the rotors nicely
The tires are good enough that their friction still exceeds the braking force. If you get bald tires, I'm sure you'll make them screech and slide.
About the ABS test, here's the why (some of it):
You don't have to punch the gas with the car in the air, btw. It will get trippy when the rear wheels are trying to get to 45mph, while the front ones are at 0mph.
Usually, when you put the car into D on the ground it starts creeping forward, right?
Same thing happens when the car is in the air. Well, wants to happen.
The transmission turns the driveshaft which in turn turns the input to the differential. The differential turns the axles like normal except there's no ground for the wheels to push on.
The wheels start spinning in air.
The brake system sees the front wheels stationary and ABS kicks in to slow the rear wheels.
This rarely ever turns out to be an equal left-right force, so you will probably see the left wheel slowing down while the right one spins faster.
Then whoa! ABS sees the right wheel spinning faster so it sporadically kicks in to slow it down and the left one is momentarily faster.
The ABS light will probably be flashing, and SLIP as well (cuts engine power)
You can go pop your hood and listen to the ABS unit doing its thing. The whole process makes a lot of unnerving sounds, but hey, it proves that it works.
Edit:
This test might be pointless on the Y50. I tried it while recording video and there wasn't as much magic to show. The TCS system cuts power (SLIP light flashes) and limits the tach to 1,000 RPM.
Other than that, I couldn't trigger the ABS light to come on. The ABS pump works no doubt (you can hear it) but even stopping one wheel by hand doesn't seem to anger it enough to pulsate left-right.
I was going off memory of what should happen. The Y34 was a little more predictable and from what I had seen, the Y50 wasn't set up that much different.
What I'd advice is to not worry about the ABS system. You'll know it's working for sure when you hit a patch of black ice
The pads are grabbing the rotors nicely
The tires are good enough that their friction still exceeds the braking force. If you get bald tires, I'm sure you'll make them screech and slide.
About the ABS test, here's the why (some of it):
You don't have to punch the gas with the car in the air, btw. It will get trippy when the rear wheels are trying to get to 45mph, while the front ones are at 0mph.
Usually, when you put the car into D on the ground it starts creeping forward, right?
Same thing happens when the car is in the air. Well, wants to happen.
The transmission turns the driveshaft which in turn turns the input to the differential. The differential turns the axles like normal except there's no ground for the wheels to push on.
The wheels start spinning in air.
The brake system sees the front wheels stationary and ABS kicks in to slow the rear wheels.
This rarely ever turns out to be an equal left-right force, so you will probably see the left wheel slowing down while the right one spins faster.
Then whoa! ABS sees the right wheel spinning faster so it sporadically kicks in to slow it down and the left one is momentarily faster.
The ABS light will probably be flashing, and SLIP as well (cuts engine power)
You can go pop your hood and listen to the ABS unit doing its thing. The whole process makes a lot of unnerving sounds, but hey, it proves that it works.
Edit:
This test might be pointless on the Y50. I tried it while recording video and there wasn't as much magic to show. The TCS system cuts power (SLIP light flashes) and limits the tach to 1,000 RPM.
Other than that, I couldn't trigger the ABS light to come on. The ABS pump works no doubt (you can hear it) but even stopping one wheel by hand doesn't seem to anger it enough to pulsate left-right.
I was going off memory of what should happen. The Y34 was a little more predictable and from what I had seen, the Y50 wasn't set up that much different.
What I'd advice is to not worry about the ABS system. You'll know it's working for sure when you hit a patch of black ice
Re: I have no ABS or light.
TDot,
I hope by now you've been able to observe what I was trying to explain in words (you know, winter and all), but these videos might help further. They cover some of the basics, and summarily indicate that you should never see your ABS light in normal operation.
I hope by now you've been able to observe what I was trying to explain in words (you know, winter and all), but these videos might help further. They cover some of the basics, and summarily indicate that you should never see your ABS light in normal operation.
Re: I have no ABS or light.
It seems it was my brake pads. I decided to change all the pads and I got my pulsating back. It seems it was primarily the rear inside pad. Now I'm waiting until the next time I need to change the pads to see if I have a seized caliper piston on the rear left based on the wearing. Thanks.
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