Focus CMax ABS light on

dr.fuzzenstein

As in the title, 06 Cmax, ABS light is on intermittently. It seems to be worse in wet weather, so it seems to point towards one of the sensors on the wheels, in fact it's most likely, since it has shown up after wheelbearing and sensor replacement.
Question is:
What diagnostic tool can I use to diagnose ABS faults on a Ford? I already have one of the famous €5 Bluetooth OBD adapters from Ebay and Torque, but that combination cannot even read ongoing engine faults, let alone ABS ones.

dr.fuzzenstein

Oh dear...

Special Circumstances

Is that one of the cars that had the ABS module made by summer students? Some volvos etc?

dr.fuzzenstein

Special Circumstances wrote: »

Is that one of the cars that had the ABS module made by summer students? Some volvos etc?

No idea, wouldn't even know where to find it.
I'm mainly looking for suggestions what tool at a reasonable price would be best suited for reading error codes from the ABS system on a Ford Focus.
I know Fords in general are weird that way, you can get a code reader that will do most cars and it will refuse to read Fords, or rather the Ford will refuse to be read.

PukkaStukka

ABS module on the Cmax is usually very reliable and isn't anything like that horrid Volvo yoke...

If you have a decent ELM cable OP, download FORSCAN for Windows from here

I've used it on my Cmax and it gives the manufacture specific non OBD codes that the bread and butter scan tools won't give you

I'd say that one of your wheel sensors is faulty or has a suspect connection....

dr.fuzzenstein

Thanks. Yes, dodgy sensor or connection most likely, since those are the only things that were fiddled around with.
The technicians mantra: retrace your steps.

dr.fuzzenstein

OK, today first try.
Downloading and installing the FORscan software on my laptop, digging out and installing an ancient Surecom bluetooth adapter and testing if this combination will work. I have all the necessary bits lying around so I got nothing to lose by trying it out.
I'll report back.

dr.fuzzenstein

Even I can scarcely believe it, it worked!
I cobbled together a solution from FORscan (free),a 10 year old Bluetooth adaptor and a €5 OBD Bkuetooth dongle from Amazon (or Ebay, it's a few years old).
Here's the readout:

DTC's in ABS C1235-A0, C1144-A0

Right rear weheel sensor

speed indicator and missing tooth tone ring.

So, right rear sensor fooked. Up with the car and it's getting greasy time.

Pukka Stukka, I owe you a pint at the very least. Very many thanks.

Stoolbend

Was it that bearing that was replaced?

Rear bearings for them usually come as a sealed unit with a new sensor installed.

dr.fuzzenstein

Stoolbend wrote: »

Was it that bearing that was replaced?

Rear bearings for them usually come as a sealed unit with a new sensor installed.

I bent a pin on the new sensor and put the old one back in. Also, the connector is pretty beat up. I took it off, cleaned all the contacts and put it back together with the addition of tape and some copper grease. If that doesn't work, new cable and sensor after that I'm looking at a new hub, but I'm optimistic it won't have to go this far. Just putting it back together and quick test drive and well see.

dr.fuzzenstein

OK, just back from town. I had cleaned and checked everything, so the cable and the contacts are verified good.
ABS light still comes on with the same error codes.
What is interesting about it, it mentions a Right Rear Tone Ring Missing Tooth Fault. This points at sensor or even the entire hub. Here's the readout:
(checking out http://www.aa1car.com/library/diagnosing_abs_wheels_speed_sensors.htm at the moment)

===ABS DTC C1235-A0===
Code: C1235 - The right rear wheel speed sensor input signal missing or the signal is not plausible.

Status:
- Previously Set DTC - Not Present at Time of Request
- Malfunction Indicator Lamp is On for this DTC

Module: Anti-Lock Brake / Traction Control Module

Diagnostic Trouble Code details

The right rear wheel speed sensor input signal missing or the signal is not plausible.

The code is set normally when the speed from one sensor differs from the speed on the other three sensors. The vehicle speed must exceed 40 kph (25 mph) for this code to be set.

A fault has been reported. At some time a wheel speed signal has been out of range. The possible causes are as follows:

Damaged wheel speed sensor.

Sensor air gap too large.

The vehicle has been towed on two wheels.

A road wheel has been dynamically balanced on the vehicle while the IN2IGN iwas in position II or shortly after IN2IGN off.

The vehicle has been driven on a two wheel rolling road.

There is a short duration intermittent open circuit on the sensor wiring.

The vehicle has been accident damaged or abused (eg. rolled spun parking brake turns etc.)

The tires installed have varying outside diameters.

A wheel bearing is worn or loose.

Additional Information

The ABS lamp should be illuminated.

The ESP lamp should be illuminated.

There will be an ESP malfunction warning displayed on the driver information text panel.


===END ABS===

===ABS DTC C1144-A0===
Code: C1144 - Right Rear Tone Ring Missing Tooth Fault

Status:
- Previously Set DTC - Not Present at Time of Request
- Malfunction Indicator Lamp is On for this DTC

Module: Anti-Lock Brake / Traction Control Module

Diagnostic Trouble Code details

Right Rear Tone Ring Missing Tooth Fault


===END ABS===

pablo128

If you activate the abs light by acting the maggot, wheelspins etc, it will reset itself after a few minutes driving. If it stays on, then there's a problem.

Now on some hubs, you can see the abs ring, but others have them internally. There's a special magnetic card you can use to check this type of hub. https://www.google.ie/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=0CCAQFjAAahUKEwjNlvWm1r3HAhVHGtsKHUzIAbg&url=http%3A%2F%2Fwww.techtalk.ie%2Findex.php%2Fntn-snr-offers-tips-on-fitting-active-sensor-bearings%2F970&ei=AO_YVc2WDse07AbMkIfACw&usg=AFQjCNHMwXP1X-fUkG6KJ6eSKlGndUQ81w&sig2=ETEIM0qaCliaKSw57BrfTQ
I think that's the type you have.

PukkaStukka

I'd keep the copper grease well away from any cables and connectors for a start. That has been known to affect the sensors and the signals they produce

I've not mucked about with the live data available in FORSCAN for ABS, but can you get the speed data for each wheel (comes up in a graph for each one I think) and see if anything at all is coming from faulty corner when the car is driven?

Also after you clear the DTC, when does it reoccur? Is it with KEY on or when driving?

dr.fuzzenstein

PukkaStukka wrote: »

I'd keep the copper grease well away from any cables and connectors for a start. That has been known to affect the sensors and the signals they produce

I've not mucked about with the live data available in FORSCAN for ABS, but can you get the speed data for each wheel (comes up in a graph for each one I think) and see if anything at all is coming from faulty corner when the car is driven?

Also after you clear the DTC, when does it reoccur? Is it with KEY on or when driving?

I have not tried this when in motion, for that I would have to have someone else driving with me monitoring the graphs as a passenger, it's just safer that way. :pac: But that sounds like a very good idea, will try this out the next time me and the OH drive to Limerick. I got the mobile version of Forescan to work, so no laptop required, my phone should be able to do that.
The fault actually clears itself, what happens is, it comes on while driving, ABS light will then be on on restart as well, once I get moving, it goes off again. Sometimes it could stay off for days, other times it comes on within a few miles.
If the ABS light stays off, it will also be off when I restart the car.
I have not yet cleared the DTC.

PukkaStukka

Can you swap the two rear sensors around and see if the fault moves? If it moves, it looks like sensor / cable / connection. If it persists with a fault at the same wheel, it's hub or bearing / wiring or ABS ECU. I'll run your fault code via a ford techie I know and if they can shed any light on it....

dr.fuzzenstein

PukkaStukka wrote: »

Can you swap the two rear sensors around and see if the fault moves? If it moves, it looks like sensor / cable / connection. If it persists with a fault at the same wheel, it's hub or bearing / wiring or ABS ECU. I'll run your fault code via a ford techie I know and if they can shed any light on it....

Thank you very much, great suggestion.

PukkaStukka

dr.fuzzenstein wrote: »

Thank you very much, great suggestion.

Assuming of course the left sensor cooperates when you try to remove it!

dr.fuzzenstein

PukkaStukka wrote: »

Assuming of course the left sensor cooperates when you try to remove it!

I find it helps if I swear at it very loudly in German. "Komm raus du Schweinehund!"

PukkaStukka

dr.fuzzenstein wrote: »

I find it helps if I swear at it very loudly in German. "Komm raus du Schweinehund!"

so ist das leben mein freund!:)

dr.fuzzenstein

After a bit of scouting around my lovely, clean, tidy and well organised garage (aka the dinghy sh*tehole), I was able to locate another ABS sensor lying around left over from when I replaced the rear hubs.
So I swapped the sensors and took it for a brief spin. The ABS light went out and stayed out, but that was only a very short spin down the road. If it is still off tomorrow after going to Limerick and coming back, then I will be cautiously optimistic.
Chuffed at that, replacement sensor would be 40 squid. A lot of money if you're not sure. And the turbo is wining, so that is €360 coming down the line.

PukkaStukka

dr.fuzzenstein wrote: »

After a bit of scouting around my lovely, clean, tidy and well organised garage (aka the dinghy sh*tehole), I was able to locate another ABS sensor lying around left over from when I replaced the rear hubs.
So I swapped the sensors and took it for a brief spin. The ABS light went out and stayed out, but that was only a very short spin down the road. If it is still off tomorrow after going to Limerick and coming back, then I will be cautiously optimistic.
Chuffed at that, replacement sensor would be 40 squid. A lot of money if you're not sure. And the turbo is wining, so that is €360 coming down the line.

Fingers crossed that you have the ABS issue sorted. Before you go reefing the turbo out, remove the air intake hose between it and the MAF, and check the tips of the impeller in the turbo. If they are bent then the bearing behind it is shot. If it's ok, you might have a leak in the air intake somewhere or something belt driven that's making the whine. Unlikely to be the turbo IF it has been serviced properly

dr.fuzzenstein

PukkaStukka wrote: »

Fingers crossed that you have the ABS issue sorted. Before you go reefing the turbo out, remove the air intake hose between it and the MAF, and check the tips of the impeller in the turbo. If they are bent then the bearing behind it is shot. If it's ok, you might have a leak in the air intake somewhere or something belt driven that's making the whine. Unlikely to be the turbo IF it has been serviced properly

We shall see.
The car has done 340 km, so I figured the turbo is due a rebuild, wear and tear will catch up with it I guess.
But I will try your suggestion first, no point throwing money away.

dr.fuzzenstein

So far, so good. The ABS light has never stayed off all the way to work, cautiously optimistic.

dr.fuzzenstein

PukkaStukka wrote: »

Assuming of course the left sensor cooperates when you try to remove it!

Oddly prophetic those words actually. Have you experience with that sort of thing? It was a bolt with a hex head and need I say the hex had rusted and worn away. Nothing would grip, it all just turned loosely whilst eating away more and more metal.
In the end I had to crawl under the car (no lift, no pit, just axle stands and jack), unbolt the shock, go in there with a vice grip, grab the nut, give it a quarter turn, release, quarter turn and so on. Due to lying on my back, the awkward angle, dust falling into my eyes and very limited space for the vice grip, progress was slow, like a quarter turn every 30 seconds with a lot of slipping of the vice grips, swearing, neck getting tired and so on. But I was NOT going to remove the entire hub just to undo one tiny bolt!
Then 20 minutes searching for a bolt with roughly the same thread. The one I found was not much better than the one it replaced.
So here's hoping the light will now stay out for good. The whole thing took me maybe 2 hours.

PukkaStukka

I have swapped ABS sensors on other cars before and given that the sensors and bolts are exposed constantly to mud and water, I have found that they are not amenable to being removed. Sometimes the amount of brute force necessary to extract them results in them being wrecked. In your case and given the ordeal you had in removing it, I would've given up bought a new sensor rather then risk damaging that one. Hence me warning that you get it to cooperate when you try to move it!

dr.fuzzenstein

Well, I kept going because I did have a replacement sensor, even if it wasn't a new one.
Anyways, so far, so good. Drove to work and back, about 120 km in total and ABS light has stayed off, so things are looking good.