Technical Let there be light! Er, not that one...

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Technical Let there be light! Er, not that one...

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Arnt lights pretty? Apart from the ABS one which has waved at me for a few days.😡

I'm guessing it's not a wheel sensor, as it comes on before the car moves.

It came on once a month back, then stayed off until the last few days when it came on permanently for 2 days.

Then it was off again yesterday...🙄

Am I correct in assuming a problem with the ABS module or pump?
 
Arnt lights pretty? Apart from the ABS one which has waved at me for a few days.😡

I'm guessing it's not a wheel sensor, as it comes on before the car moves.

It came on once a month back, then stayed off until the last few days when it came on permanently for 2 days.

Then it was off again yesterday...🙄

Am I correct in assuming a problem with the ABS module or
Hi,

Actually it could be a wheel sensor or associated wiring. Often ABS systems self check includes wheel sensor/ wiring before the vehicle moves (some bmw motorcycles an exception but lets not get into that).

Get fault codes read from abs system to avoid guessing and visual check of wheel sensor wiring.

Good luck

Let us know outcome

Regards
Jack
 
Arnt lights pretty? Apart from the ABS one which has waved at me for a few days.😡

I'm guessing it's not a wheel sensor, as it comes on before the car moves.

It came on once a month back, then stayed off until the last few days when it came on permanently for 2 days.

Then it was off again yesterday...🙄

Am I correct in assuming a problem with the ABS module or pump?
short answer is it could be anything not just the ABS module (pump is built in)

Without reading the codes its going to very tricky to diagnose

Wheel bearings, sensors, wiring, brushes in the motor, sticking valve, flat tyre and many more

reading codes can be done quite a few ways , multiecuscan plus cable adaptors, Delphi, WOW
with multiplexer all work and tested by me. Most cheap hand held scanners will only read the engine module and useless for this but there are others that will connect to the other modules but I haven't used them.

another alternative is to pay a garage to read the code

always worth doing the free and easy first

tyres correct pressure
tyres all the same size
wheel nuts tight
brake fluid visual inspection
abs sensors to main wiring not corroded or damaged
no metal dust stuck to the end of the ABS sensor
when it fails can you hear the ABS self test

After that you are into no option except reading the code unless I have missed something out
 
Mine did this to me a few years back, just once, then again last week. I'd turned the key to start a little too early, and it got upset. No codes.
When you first turn the key to ign on, wait, look and listen. Allow the fuel pump to raise the pressure and stop, allow the display to declare the self-test ok. As pump stops, turn key to start.
If you turn the key straight from off to start, it will often display the immobiliser warning.
I'd turned to start, probably only half way through the self-test. During starting, many of the circuits are disabled, to remove some of the potential current drains, so interrupting the self-test gets the computers all stroppy. I'm guessing the ABS hadn't finished testing, so got upset with me.

If that doesn't fix it, you'll need to get the codes read, as above.
 
Thanks all,

Speedo works fine. There is a whining wheel bearing, hard to hear above the general din at times!

I'll have the battery checked - brake fluid fine, all tyres the same and good condition. I think this car is pretty tired all round, I don't really think it's worth spending much money on sadly.
 
ABS sensors are cheap. As you say ABS pumps are not, but the latter is also very reliable. It could be a magnetic strip that creates the pulse for the sensor to read. Hey! it might even be that noisy wheel bearing has lost its mag strip.
 
Thanks all,

Speedo works fine. There is a whining wheel bearing, hard to hear above the general din at times!

I'll have the battery checked - brake fluid fine, all tyres the same and good condition. I think this car is pretty tired all round, I don't really think it's worth spending much money on sadly.
well thats some good news

the electronic board on the ABS unit is likely to be fine. The speedometer runs of the nearside front ABS sensor and has to communicate to through several devices before getting to the speedometer

If the fault had been here it would have been expensive as the ABS is coded to ECU and can't just be changed from the breakers. I believe. Haven't double checked but most cars are like this, just had to repair one for a Suzuki because it was easier than recoding

Once a fault is detected with a sensor the ABS light will come on straight away. It will self clear only when it sees 4 good signals. But also on power on the ABS does a power on self test it pressurises the system and operates the solenoids, A common faults are the motor not to spin (the one I have just repaired) or a faulty pressure sensor.

we need some way to eliminate parts of the system. The easy way is to read the code

When the fault is permanent you could get someone to turn the ignition on while you listen to the ABS motor. You should hear a buzz from the motor. If its not spinning the motor brushes have got jammed.

The ABS sensor reads directly from the wheel bearing. If its worn or overheating it will also cause an ABS fault

one thing I missed on things to check. The ABS sensor is plastic. Its not uncommon for them to crack where they bolt in leading to intermittent problems
 
A sensor code will tell you which one is faulty. This will appear at ignition on.
A code that appears only when moving (speed circuit) could be as cheap as a mag strip on a wheel - again the code should tell you.
(Rear wheel bearings are around £30 and easy to fit when you have a 600mm breaker bar and socket.)

This is a list of generic OBD2 codes from https://www.aa1car.com/library/abscodes.htm
C0035 - Left Front Wheel Speed Circuit Malfunction​
C0040 - Right Front Wheel Speed Circuit Malfunction​
C0041 - Right Front Wheel Speed Sensor Circuit Range/Performance (EBCM)​
C0045 - Left Rear Wheel Speed Circuit Malfunction​
C0046 - Left Rear Wheel Speed Sensor Circuit Range/Performance (EBCM)​
C0050 - Right Rear Wheel Speed Circuit Malfunction​
C0051 - LF Wheel Speed Sensor Circuit Range/Performance (EBCM)​
C0060 - Left Front ABS Solenoid #1 Circuit Malfunction​
C0065 - Left Front ABS Solenoid #2 Circuit Malfunction​
C0070 - Right Front ABS Solenoid #1 Circuit Malfunction​
C0075 - Right Front ABS Solenoid #2 Circuit Malfunction​
C0080 - Left Rear ABS Solenoid #1 Circuit Malfunction​
C0085 - Left Rear ABS Solenoid #2 Circuit Malfunction​
C0090 - Right Rear ABS Solenoid #1 Circuit Malfunction​
C0095 - Right Rear ABS Solenoid #2 Circuit Malfunction​
C0110 - Pump Motor Circuit Malfunction​
C0121 - Valve Relay Circuit Malfunction​
C0128 - Low Brake Fluid Circuit Low​
C0141 - Left TCS Solenoid #1 Circuit Malfunction​
C0146 - Left TCS Solenoid #2 Circuit Malfunction​
C0151 - Right TCS Solenoid #1 Circuit Malfunction​
C0156 - Right TCS Solenoid #2 Circuit Malfunction​
C0161 - ABS/TCS Brake Switch Circuit Malfunction​
C0221 - Right Front Wheel Speed Sensor Circuit Open​
C0222 - Right Front Wheel Speed Signal Missing​
C0223 - Right Front Wheel Speed Signal Erratic​
C0225 - Left Front Wheel Speed Sensor Circuit Open​
C0226 - Left Front Wheel Speed Signal Missing​
C0227 - Left Front Wheel Speed Signal Erratic​
C0229 - Drop Out of Front Wheel Speed Signals​
C0235 - Rear Wheel Speed Signal Circuit Open​
C0236 - Rear Wheel Speed Signal Circuit Missing​
C0237 - Rear Wheel Speed Signal Erratic​
C0238 - Wheel Speed Mismatch​
C0241 - EBCM Control Valve Circuit​
C0245 - Wheel Speed Sensor Frequency Error​
C0254 - EBCM Control Valve Circuit​
C0265 - EBCM Relay Circuit​
C0266 - EBCM Relay Circuit​
C0267 - Pump Motor Circuit Open/Shorted​
C0268 - Pump Motor Circuit Open/Shorted​
C0269 - Excessive Dump/Isolation Time​
C0271 - EBCM Malfunction​
C0272 - EBCM Malfunction​
C0273 - EBCM Malfunction​
C0274 - Excessive Dump/Isolation Time​
C0279 - Powertrain Configuration Not Valid​
C0281 - Brake Switch Circuit​
C0283 - Traction Switch Shorted to Ground​
C0284 - EBCM Malfunction​
C0286 - ABS Indicator Lamp Circuit Shorted to B+​
C0287 - Delivered Torque Circuit​
C0288 - Brake Warning Lamp Circuit Shorted to B+​
C0290 - Lost Communications With PCM​
C0292 - Lost Communications With PCM​
C0291 - Lost Communications With BCM​
C0297 - Powertrain Configuration Data Not Received​
C0298 - Powertrain Indicated Traction Control Malfunction​
C0300 - Rear Speed Sensor Malfunction​
C0305 - Front Speed Sensor Malfunction​
C0306 - Motor A or B Circuit​
C0308 - Motor A/B Circuit Low​
C0309 - Motor A/B Circuit High​
C0310 - Motor A/B Circuit Open​
C0315 - Motor Ground Circuit Open​
 
Mine did this to me a few years back, just once, then again last week. I'd turned the key to start a little too early, and it got upset. No codes.
When you first turn the key to ign on, wait, look and listen. Allow the fuel pump to raise the pressure and stop, allow the display to declare the self-test ok. As pump stops, turn key to start.
If you turn the key straight from off to start, it will often display the immobiliser warning.
I'd turned to start, probably only half way through the self-test. During starting, many of the circuits are disabled, to remove some of the potential current drains, so interrupting the self-test gets the computers all stroppy. I'm guessing the ABS hadn't finished testing, so got upset with me.

If that doesn't fix it, you'll need to get the codes read, as above.
not sure why some Fiats do this but its real, I have seen a fairly new 500 on a YouTube video doing this
Neither my Punto or 3x Pandas have had this "feature". You can jump in and turn the key as fast as you like.
Needs someone to get to the bottom of this. But it would be difficult unless the fault was regular. Same with the kangarooing
 
another bit I missed out


depending on model. A faulty brake switch will throw a ABS error . These switches fail all the time. Not sure which models. it seem to be models with hill assistance mainly
 
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Thanks all for the brilliant replies, I shall have to look at the most cost effective way of reading the fault codes. 🙄

I used to have a little elm 327 Bluetooth thingy that worked with a phone app, worked well on a lot cars, but can't find it ...
 
Thanks all for the brilliant replies, I shall have to look at the most cost effective way of reading the fault codes. 🙄

I used to have a little elm 327 Bluetooth thingy that worked with a phone app, worked well on a lot cars, but can't find it ...
If you find your bluetooth thingy, it will probably only read powertrain codes, almost certainly won't read Fiat ABS codes.
What is needed is MultiECUscan. Quite a few people on here have this, and many are likely to help, if only we knew where you were. (Few people seem to fill in the location part of their profile.)
 
If you find your bluetooth thingy, it will probably only read powertrain codes, almost certainly won't read Fiat ABS codes.
What is needed is MultiECUscan. Quite a few people on here have this, and many are likely to help, if only we knew where you were. (Few people seem to fill in the location part of their profile.)
correct you will need the minimum of an additional "ADAPTER CABLE 1" (green) to work with multiecuscan (MES) as the ABS module isn't on the same pin in the diagnostic connector as the ECU module. MES doesn't work with every Bluetooth adaptor

early 1.1 and 1.2 ABS are fine and can be read by even the free version of MES

However the later ECO versions can not be read at all by MES even full version according to there website they dont specify a year I am guessing up to 2009 but could be wrong

I have read a 2010 ABS via Delphi and WOW so most garages should be able to read ABS of an ECO fine. I have read a 1.1 06 and 1.2 05 using MES fine
 
I got this set from Car Bits South Wales. It works fine with MES on a PC laptop. Sadly it wont work on my preferred MacBook but I run an old Windoze Netbook for the job. https://www.ebay.co.uk/itm/202431829491?hash=item2f21e095f3:g:sQEAAOSwBFpblUck

You do however need to check that your OBD port is alive. I went chasing software errors only to find that a faulty relay (probably) was the problem. It self resolved after every fuse and relay in the car hade been pulled and replaced a couple of times so I never discovered the real culprit.
 
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