This episode is about a 2011 Ford Edge and why its ABS warning light was coming on. The problem is tied to a part that helps the car measure wheel speed so the anti-lock brakes can work correctly.
A diagnostic is how the shop figures out why the ABS warning is happening. They check the ABS sensors and electronics to locate the specific faulty part.
A tone ring is a ring on the wheel that has little notches. Those notches help the ABS sensor “count” wheel speed so the car knows what each wheel is doing.
To modulate (in ABS terms) means the system rapidly adjusts brake pressure at a specific wheel to prevent lockup. By reducing pressure when a wheel slows too much, then restoring it as traction returns, ABS keeps the tire rolling and steering possible.
A skid happens when the tires lose grip and the car starts sliding. The episode’s point is that ABS helps prevent that lockup so you can keep control, especially in a corner.
The axle shaft is the part that spins the front wheel. Here it’s taken out because a metal ring on it has broken, and that ring is needed for the car to correctly detect wheel speed for ABS.
Rust is corrosion that eats away at metal and can also make it swell or get rough. In this case, rust growth helps break the tone ring, and rust pitting can also make it hard for a new ring to fit correctly.
Wheel speed is how fast the wheel is turning. ABS uses that information to decide when a wheel is about to lock up, and a broken tone ring can make the car think the wheel speed is wrong.
All-wheel drive means the car can send power to more than two wheels. The shop is saying that because there are multiple parts involved, more than one could eventually wear out—but they don’t replace the others until they’re actually broken.
Shock absorbers help smooth out the ride by controlling how the suspension moves. The shop uses them as an example of a case where replacing one side might change how the car feels.
Brake pads are the parts that squeeze against the brake rotors to stop the car. The shop is saying that with brake pads, mechanics often replace things in a balanced way, but this situation is different.
The ABS light is a warning on the dashboard for the car’s anti-lock braking system. If it’s not on after the fix, that’s a good sign the system is working normally.
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Hi, it's Mark Bossard. I'm here with Bernie Pawlik, Pawlik Automotive in Vancouver.
Vancouver's best auto service experience. We're talking cars. How you doing Bernie?
Doing very well. So today's guest is a 2012 Jeep. Hi, it's Mark Bossard. I'm here with Bernie
Pawlik, Pawlik Automotive in Vancouver, BC, Canada. Vancouver's best auto service experience.
We're talking cars. How's it going Bernie? Doing very well. So today's guest is a 2011 Ford Edge.
What was happening with this vehicle? So this vehicle came to us as a new client. We did a
B service on it, which is an oil change and a full vehicle inspection. And one of his concerns was
that the ABS light would come on the vehicle. So we proceeded to do a diagnostic on the ABS system
and found that the right front tone ring for the ABS was broken.
So what is a tone ring? So it is basically a ring that has notches on it. And as the wheel turns,
it's on the axle. As the axle turns, there's an ABS sensor nearby and it sends a signal to that.
It's a magnetic pulse. So I don't know why they call it tone, but that's the term for it. It sends
a signal based on the speed of how fast the wheel is turning to the computer ABS module.
And then that feeds into the automatic braking system so that it starts to control. If you put
the brakes on the on and off of the brakes, basically faster than a human can do it.
Exactly. And so this is the critical input. There's one on each wheel. And so the computer
monitors how fast is this wheel turning in relation to the other ones. And if all of a
sudden starts turning much slower while you're braking, then it'll turn the ABS brake on. It'll
modulate it and put less brake pressure to that wheel until that wheel turns at the same speed.
Then it lets the pressure back on. All happens in fractions of a second while you're braking.
And all that means is that you can maintain control of your car even under hard braking.
Exactly. Hard braking and especially when you're going around corners. That's where it's really
most important because if the vehicle goes into a skid, it won't turn. It'll just keep going straight.
So that's where that's most critical for ABS brakes. So here's our guest. Great shape for
2011 Edge. It looks like brand new. It looks like it just rolled out of the showroom. So this car's
been really well taken care of. Even the paint gleams and shines. And how many kilometerage?
It's 154,000 kilometers. So I think that's just under 100,000 miles. 90,000 miles. Pretty young
still. What is this? So this is the right front axle shaft removed from the vehicle. And the
tone ring is lying on the ground just to the left of that arrow. The tone ring is actually
broken off the axle. And the reason why is that over time, the axle rusts. And as it rusts, it
expands. And the tone ring, I can't remember what it's made of, but it's a hard metal ring and it
actually snaps. This is not an uncommon issue on Ford. It's been a while since we've done one for
this problem. But over the years, we've seen quite a few Fords. It isn't just a Ford thing,
but it seems to be common on a lot of Ford products. And there's a close up. You can see
where the ring used to be, that sort of shiny spot. And it's rusted underneath there. So as the rust
starts to occur, it starts to expand underneath the ring. And then the ring cracks. There's the
tone ring. It's supposed to be a perfect circle. And you can see where you're moving your pointer.
It's cracked right there. So the ring, of course, doesn't spin at a proper speed. And the computer
right away notices that notes that, I should say. Interestingly enough, we turned the vehicle on and
started it in the parking lot and the ABS light was not on. But all you have to do is drive a
few feet and right away, the computer realizes something's wrong here and sets the light on.
And of course, when it does that, the system's not working. Here we have the replacement axle.
You can see the ring perfectly mounted in the right spot. That's where it should have been on
the other one. And the axle is all shiny and non-rusted in proper working order.
Couldn't you have just replaced the ring, cleaned this off and put a new ring back on here?
You can actually buy tone rings, at least you used to be able to. But here's what happens is,
if you don't clean the rust off, when you hammer the new ring on, it'll snap because the diameter
of the metal is too large. So of course, cleaning it off, we have nice wire wheels. We can power
wire wheels. We can clean that off and get rid of all that rust. But what now happens is that
diameter is now too small to hold the ring properly because as it's rusted, the metal is also pitted
and it's worn. The ring won't hold on properly. So the only real solution, you might get lucky and
it might stay on, but it's not a repair we do because we want repairs to last. So replacing the
axle, which isn't that outrageously expensive, is the way to go. And once the repair was done,
it was just one wheel. Did you check the other wheels? Oh yeah, we look at all of them. They're
all fine. And there's a possibility, of course, that next week the other one might snap. There's
four of them. So it's an all wheel drive vehicle. So there's four of them. So possibly all of them
will break over time, but it doesn't make any sense to do it while it's not broken. It might
still last for five or 10 more years. You just never know. Or it could go in a couple of weeks,
but it was fine at the time. Yeah. And there's no performance or benefit or
breaking difference in replacing them just to make sure or anything like that. Like sometimes
there is with shock absorbers, say. No, exactly. Yeah. Sometimes when you replace a certain component,
say brake pads, you don't just change the left front brake pad. You change all the front components
because you need evenness. But in this case, it's a computer input. And as long as it's working,
then it's working. And there's no cost savings to do the other side now. And after repair,
all worked just great. No ABS light. Yeah, all good. Another happy customer at Pawlik
Automotive. Yeah, we like happy customers. So if you're looking for service for your Ford products
in Vancouver, BC, Canada, the people to see are Pawlik Automotive. You can reach them online at
pawlikautomotive.com. You can book your appointment right there. Or you can call them at 604-327-7112.
You have to book ahead. They're always busy. Pawlik Automotive in Vancouver, BC, Canada.
Thanks so much for watching and listening. And thank you, Bernie. Mark.
Thank you for watching.
About this episode
A 2011 Ford Edge came in with an ABS warning light, and the diagnosis pointed to a broken right-front ABS tone ring. The hosts explain how the tone ring’s notches create a wheel-speed signal and how ABS uses those signals to modulate brake pressure. They also connect the failure to axle rust that expands and snaps the ring, sometimes only after driving a few feet. The shop replaced the axle (not a short-lived fix), and the ABS light went away.
