Yaris electrical issues

[emin-j]

Hi all, my Daughters 2014 Yaris Trend has started having some strange electrical issues lately, the abs/trc light comes on occasionally plus an annoying beep , also the Rev counter and speedometer needles are erratic plus the coolant temperature light flashes on and off !

I have OBD2 codes showing as U0073 and U0129 which are control module communication issues and could possibly a bad abs module. The front near side wheel speed sensor did show as a possible problem so I removed it and cleaned it although it was quite clean and in good condition plus I checked the wiring up to the connection above the wing liner and clean terminals with electrical contact cleaner, today I checked all under bonnet connectors and earth’s, tested all fuses , removed the Battery and disconnected the abs module plug , checked for bent pins etc plus cleaned with contact cleaner.

My Daughter collected her car and within 10 minutes of driving the abs light and beeping started again !

Im out of ideas now, has anyone had a similar issue ?

[flash22]

Remove the gauge cluster, check the plug and socket on the back inc pin fitment, Can you talk to the ABS module its self (not the main ecu) and read the codes from it ?

[emin-j]

50 minutes ago, flash22 said:

Remove the gauge cluster, check the plug and socket on the back inc pin fitment, Can you talk to the ABS module its self (not the main ecu) and read the codes from it ?

Have gone into the abs system using Toyota techstream and everything seems to check out ok , can operate abs pump and check abs sensors no problem, will check plugs in back of gauges though 👍

what I can’t understand is the connection (no pun intended) between the rev counter and speedometer being erratic and abs codes.

[scar]

Whilst this won’t be of any help to you it’s shows how random faults can fool you.

My wife had a Audi TT. I changed the air filter at a service and when I went to start the car I got a warning there was an issue with the 4 wheel drive system. Bugger I thought, what have I done .

Well you had to disconnect the MAF electrical connector to remove the air box cover. I hadn’t reconnected it. Put it back and all was well.

So whats the relationship between an air filter and a 4 wheel drive system ? None that I know of.

Hope you get your issue sorted.

[stantheman1]

What's the Battery voltage ( with reference to chassis and again to engine)?

Have you cleared the codes and did the same codes reappear, if so check freeze frame data to see what conditions the faults are triggering?

Check pins 6 and 14 on DLC with an Ohm meter with ignition OFF (Use paper clips or similar to 'front probe' the dlc connector), resistance should read approx 60 ohms.

[emin-j]

38 minutes ago, stantheman1 said:

What's the battery voltage ( with reference to chassis and again to engine)?

Have you cleared the codes and did the same codes reappear, if so check freeze frame data to see what conditions the faults are triggering?

Check pins 6 and 14 on DLC with an Ohm meter with ignition OFF (Use paper clips or similar to 'front probe' the dlc connector), resistance should read approx 60 ohms.

Battery voltage 12.53v codes can be cleared but as fault is intermittent can reappear 24 hours or more later when abs/trc warning light shows again.

[bathtub tom]

I'd start from basics. Remove Battery, clean terminals and ALL connections, particularly earths. Then proceed from there.

[Madasafish]

As Bathtub Tom above.

First place to start on ALL electrical issues.

[flash22]

The VSS is generated from the abs sensor, the abs talks to the cluster and the ECU and can cause comm's codes, I had an issue with mine the where the speedo would drop out, that was a pin fitment issue with the plug on the cluster and was completely intermittent

that would also explain the flickering lights, the rev counter signal comes from the ecu so that points to the cluster as well

 

edit. As you have 2 comm's codes something is taking down the can bus intermittently

[emin-j]

10 hours ago, bathtub tom said:

I'd start from basics. Remove battery, clean terminals and ALL connections, particularly earths. Then proceed from there.

Thanks , have done all that , it’s a intermittent connection somewhere but not easy to locate 👍

[emin-j]

14 minutes ago, flash22 said:

The VSS is generated from the abs sensor, the abs talks to the cluster and the ECU and can cause comm's codes, I had an issue with mine the where the speedo would drop out, that was a pin fitment issue with the plug on the cluster and was completely intermittent

that would also explain the flickering lights, the rev counter signal comes from the ecu so that points to the cluster as well

Thanks, I’ll have a look at that , my daughter texted me to say the power steering warning light also came on for a short time 🙄 . When she turns the car off and then restarts the warning lights disappear and all’s good for a while then suddenly lights reappear, haven’t heard a beeping with an abs light before 🤷‍♂️ obviously a intermittent connection somewhere but not easy to diagnose.

[stantheman1]

21 hours ago, emin-j said:

Battery voltage 12.53v codes can be cleared but as fault is intermittent can reappear 24 hours or more later when abs/trc warning light shows again.

Have you seen any freeze frame data?

[stantheman1]

9 hours ago, emin-j said:

Thanks, I’ll have a look at that , my daughter texted me to say the power steering warning light also came on for a short time 🙄 . When she turns the car off and then restarts the warning lights disappear and all’s good for a while then suddenly lights reappear, haven’t heard a beeping with an abs light before 🤷‍♂️ obviously a intermittent connection somewhere but not easy to diagnose.

Freeze frame data could hold a clue.

[emin-j]

1 hour ago, stantheman1 said:

Freeze frame data could hold a clue.

Thanks, I’ll grab some screenshots asap 

[emin-j]

On 5/3/2021 at 8:56 PM, emin-j said:

Thanks, I’ll grab some screenshots asap 

Here’s some screenshots but unfortunately some wouldn’t upload, being intermittent it’s difficult to locate, obviously a can bus communication issue.

[stantheman1]

Have you managed to check the resistance across pins 6 and 14 yet? 

[flash22]

They are all historic faults none pending or current (apart from 1) - thay are all comm's issues as they are not current it could have just been low Battery voltage or a bad ground from the battery/loose terminal/grotty terminal

 

PS. if you want to take screenshots or capture parts of the screen use Snip and Sketch (press the windows button  - then type s n)

[flash22]

Go into ABS Live - click on the U0073 - click the data list button and look for EFI communication open and Body ECU communication Open and see the status

 

 

 

[emin-j]

9 hours ago, stantheman1 said:

Have you managed to check the resistance across pins 6 and 14 yet? 

Not as yet, I know target is around 60ohms

[emin-j]

7 hours ago, flash22 said:

Go into ABS Live - click on the U0073 - click the data list button and look for EFI communication open and Body ECU communication Open and see the status

 

 

 

Thanks flash22 I’ll check that.

I cleared all the codes yesterday and took it for a drive the ABS/TRC , Power steering, Brake warning light, temperature light was flashing and speedometer needle was erratic, couldn’t check for codes again as the daughter needed the car .

[Sulav]

On 5/16/2021 at 11:15 PM, emin-j said:

Thanks flash22 I’ll check that.

I cleared all the codes yesterday and took it for a drive the ABS/TRC , Power steering, Brake warning light, temperature light was flashing and speedometer needle was erratic, couldn’t check for codes again as the daughter needed the car .

I have same issue with my Yaris 2012. What is the solution for this?

[flash22]

all you can do is pull the codes and go from there