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The 16352-014 code, from experience, means faulty ABS control unit. I believe ABS sensor or reluctor problems will give you different codes.

Since it's an intermittent fault you might try cleaning the ABS unit connector contacts with electrical contact cleaner before going down a more expensive route. I doubt it will make any difference but you never know. Access to the unit is probably more difficult on LHD vehicles.
 
A code reader only gives you so much information and it doesn't always tell you the exact fault. There are at least 3 categories of ABS fault I've had experience of: In category 1 the ABS unit itself is working and fully functional but its input from (e.g wheel) sensors is bad. VCDS or equivalent V.W compatible diagnostics decodes fault codes into plain English and will tell you which wheel sensor is faulty. If after ignition on there's no fault code logged or ABS warning lit until you drive, you can be fairly certain it's a wheel sensor problem unless the sensor wiring or electronics are faulty. The ABS controller checks these at key on.

The second fault category is much harder to solve and often requires an expensive replacement ABS control module: At key on and engine start the dash ABS and steering warnings come on straight away even after clearing faults. First make sure the fault code doesn't relate to wheel sensors or their wiring and they pass the static key on check. VCDS can give some fault problems internal to the unit. One fault is the brake line pressure sensor. This is a piezo type pressure sensor measuring a wide range of high brake line pressures. On older V.W cars this sensor was an external part and it's logical for V.W compatible diagnostics to measure it. Unfortunately on EOS ABS modules they embedded this sensor in the pressure block and it's virtually impossible to replace without workshop machines. But AFIK, the pressure block is available as a replacement part. VCDS can measure brake pedal line pressure. If the VCDS measuring block shows zero and doesn't change when the pedal is pressed, this fault is confirmed

The 3rd category is left for intermittent ABS faults inside the module electronics. These could occur at random times at key on after clearing faults and are not caused by wheel or brake pressure sensor inputs. This type of fault would be hard to find because the smd electronic board is extremely complex. Heating the board with hot air whilst monitoring for fault codes might find something. You can do this kind of test with the module plugged in and hydraulics disconnected. The ABS connector and connectors between the motor and the controller board would be the easiest thing to check and clean first. The original ABS units were replaced under recall in some countries. In U.K they only replaced them for free if they went faulty in the warranty period! I might expect the internal pressure sensor to fail on an older car, but not one less than 3 years old. Therefore IMHO there could have been a problem with the pcb soldering assembly causing intermittent faults?. The average DIYer won't be able to do anything and AFIK if you are certain electronics are the problem, they used to sell the board as a replacement part? If you are used to smd working, you might strike lucky using a microscope and soldering iron!

For most, it's probably easier to source a used ABS module but you have to get the correct part. They seem to be sold quite cheap because they are either compatible and work, or they don't. If your original ABS module still communicates with diagnostics and can be scanned, it's not fully dead. Extract the module header info. with module and firmware codes ASAP. If there's no communication with the module, it is probably pretty dead and beyond repair.
 
Update, I received the VCDS (Ross Tech) and the wheel speed sensors worked as advertised and no further codes. I was on vacation but needed to return to work and further trouble shooting was not an option. Long story short I took the GTI into my trusty mechanic and the ABS module needs to be replaced. Having spent 20 years in the Marine Corps as a helicopter mechanic (UN-1N / AH-1W) I enjoy working on vehicles; however, brakes are not an area I will chance when my wife is driving her beloved GTI. Luckily my M5 is running great.
Wheel Tire Car Vehicle Hood
Wheel Tire Car Vehicle Hood
Wheel Car Tire Vehicle Automotive parking light
Wheel Car Tire Vehicle Automotive parking light
 
That depends. You can have lots of training on helicopter hydraulics but that doesn't mean you will know you might need to use vacuum brake bleeding techniques on a V.W car or diagnostics to purge fluid through the ABS hydro unit? I will work on V.W brakes, but I wouldn't do anything on a helicopter without training (unless it was a toy drone). At least with a car if you get it wrong you don't fall out of the sky!

The important point is his wife is a driver and from my experience you cannot expect your wife to spot things that are wrong. They just want to push the pedal and stop. That's the difference between dealer and DIY servicing. They are trained (hopefully) to get it right and for somebody with little technical knowledge or awareness, I would always recommend regular dealer or independent garage servicing.
 
Discussion starter · #66 ·
The fun never stops with these cars. I had an issue with the brake pad sensor harness and jumped the connection on the damaged harness. The brake pad light is no longer on. I didn't drive the car for 8 weeks, but now the ABS light is on (again). The code says it is the left front wheel sensor. I may have damaged it trying to fix the brake pad wear sensor harness. Probably should not have soaked the area with brake cleaner trying to clean the area.
 
The code says it is the left front wheel sensor
That just means there's nothing being sensed or the wrong output. Diagnostic semantic description shouldn't be taken as literal, it's only basic language mean't for trained technicians to apply and interpret.
 
At least that's what is going on with mine. The recall is a software upgrade that may include a module replacement or re-grounded. That's all I know for now myself. If you've found out differently, please let me know
 
IMHO The ABS module has a design reliability issue which I don't see if diagnostics shows a wheel sensor fault. Software/firmware doesn't just 'break'? If the module has worked for years, a software modification will only affect how it works. But the piezo brake pressure sensor is a key component integrated into the unit pressure block and when that fails the ABS fault is permanent.
 
Discussion starter · #70 ·
I few months ago I started getting the brake pad wear warning. The pads were good, but the harness going to the pad sensor was broken. I wasn't sure where this harness went into the engine bay or how easy it would be to replace, so I jumped the circuit to keep the light off. I have had this random ABS light (left wheel speed sensor) for a couple of years. It would come on briefly and then go off for a couple of months. The only difference now is ABS light is staying on. The message says "00283 ABS Wheel Speed Sensor, Front Left (G47) Short Circuit to Another Valve". Is there any connection between the brake pad sensor harness and the wheel speed sensor harness?
 
The semantics used by diagnostics isn't human and you have to be cautious making a literal interpretation. A human (like you) can test wiring for short or intermittent open circuit from the wheel sensor to that big fat connector on the ABS unit. There are other possible causes.
 
Discussion starter · #72 · (Edited)
The semantics used by diagnostics isn't human and you have to be cautious making a literal interpretation. A human (like you) can test wiring for short or intermittent open circuit from the wheel sensor to that big fat connector on the ABS unit. There are other possible causes.
I have been doing a bit of research and have been conflicting answers. Do you know if the brake pad wear sensor harness is separate from the wheel speed sensor harness? Or are they part of the same harness?
 
Why do you need to keep researching for answers? Since you were skilled enough to cut through and jumper cables, you should also be able to look at a wiring harness and see how many wires are inside it? If it has 1 or 2 wires the same or a different color e.g The brake pad wear sensor, then logically the ABS sensor wires must be going a different route and you can trace the colors? Since ABS sensors are replaceable parts, they too have a connector. From memory the brake pad wear sensor is also on its own connector and only you know what wires you have been cutting?

If you really wanted to bypass the pad wear sensor, why didn't you just cut off the pad wires, leave the connectors in-situ and jumper the (yellow?) pad wear wires? At least a decent technician would see what you had done.

Since your car has 4 wheels and the other 3 have similar ABS wheel sensors, why don't you have a good look at their ABS sensor wiring, but avoid the urge of wanting to cut them!
 
Discussion starter · #74 · (Edited)
Why do you need to keep researching for answers? Since you were skilled enough to cut through and jumper cables, you should also be able to look at a wiring harness and see how many wires are inside it? If it has 1 or 2 wires the same or a different color e.g The brake pad wear sensor, then logically the ABS sensor wires must be going a different route and you can trace the colors? Since ABS sensors are replaceable parts, they too have a connector. From memory the brake pad wear sensor is also on its own connector and only you know what wires you have been cutting?

If you really wanted to bypass the pad wear sensor, why didn't you just cut off the pad wires, leave the connectors in-situ and jumper the (yellow?) pad wear wires? At least a decent technician would see what you had done.

Since your car has 4 wheels and the other 3 have similar ABS wheel sensors, why don't you have a good look at their ABS sensor wiring, but avoid the urge of wanting to cut them!
I am trying to gather information before I look at the car. I live a condo in Florida with no garage and I can not leave my car on jacks overnight in the parking. Not to mention in the middle of the day it is hotter than the surface of the sun right now, so I would like to complete any repair early in the morning in a couple of hours.

I jumped the brake pad sensor on the connector on harness side, as that is where the damage was. Jumping the pad wear wires would not have completed circuit. And I did not cut the wires, both where exposed and one was completely detached.

One question that maybe you can answer. I want to test the wheel speed sensor harness. When the key is in the on position, what should the voltage be to the wheel speed sensor?
 
Like I said, measure and compare with another one? You should see one wire at +12V wrt ground and the other wire about +11.3V wrt to ground if I remember? That's why they use an insulated 2 wire connector.

Measured across both wires, about 0.7-1V. If either wire have been shorted to ground then an expensive 'Poof' inside the ABS controller. I do know what burns out inside and have repaired one, but it's smd micro-circuitry and you probably aren't up to that?
 
Discussion starter · #78 · (Edited)
So I finally got around to replacing the wheel speed sensor, except it didn't go as planned. Everything went fine until I attempted to pull the sensor out and it broke off. So now it looks like I will be drilling the broken part with my Dremel, installing a screw and trying to pull the remaining piece out. Probably will not get to this until Sunday. Any suggestions?
 
Sounds like you are in the spiral of doom making more DIY mistakes and getting more problems? You certainly go about things the hard way. If you break through the end of your broken sensor with a screw or drill and hit the bearing, you will destroy the bearing grating if it isn't already bad.

ABS sensors have plastic bodies with 4 molded flutes that only make contact with their edges inside the steel hole. They make them from plastic to stop them seizing in with rust so people don't have to resort to butchering to get them out. Once the small retaining screw is removed, it should be just a matter of gently i.e carefully levering under the screw tab to withdraw it and never try turning or rotating it. But you've probably butchered it already if half is broken and left stuck inside?

The butchers method is to carry on butchering. The V.W professional shop method to recover from bad DIY work would be to remove the rotor, backplate and hub then knock it through the back with a drift or bolt. But your lack of skills and tools might end up with more butchery? After all this as I explained before, you could replace the sensor and it still faults because the bearing grating is damaged. But at least if you've gone this route you'll know how to take it all apart again to replace the wheel bearing. Onwards and upwards then.
 
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