Mazda6 2011 electrical power steering hard

Mortada Engineer Saudi Arabia Posted   Latest   Edited  
Delayed
Driveability
C0031-23
U0131 — Lost Communication With Power Steering Control Module
U0415 — Invalid Data Received From Anti-Lock Brake System (ABS) Control Module
Electrical Power Steering Hard To Turn Left Or Right With Icon Eps On Dashboard

I've checked powers and grounds related to EPS and EPS control unit and checked PCM can hi, low resistance and found 120 ohms and continuity test good between EPS control module and BCM and DLC and found good.

I've checked the wires related to EPS again, tow wires (white & black) from EPS control module connected to PCM (red & green)and TCM(black/red and brown) but DLC (black/red & brown ---red & green)connected to Dashboard and Body ECU, this tow group of can wires, what confused me that DLC (black/red & brown ---red & green) 4 wires twisted as indicator of can wires not connected with connector that holding the same wire color and twisted as indicator of can wires.

Attached here photo of two connectors.

I note that instrum panel lost communication with ABS and EPS control model and PCM lost communication with EPS control unit even continuity test between PCM and EPS control unit is existed at can wires.

Attached here video shows abs and check engine and steering while engine running.

0
Interesting
Dmitriy Analyst
Ontario
Dmitriy
 

Hi Mortada, if you have a Google account, would you be able to try out my experimental Powertrain CAN Diagnostics guide? Go to: …​.​com/software/AWSM Sign-in with Google, then open tab “Powertrain CAN Diagnostics” at the bottom of the screen: diag​.​net/file/f1xbici6n… ​ See where it takes you, post the transcript. Thanks!

+1
Ð Awarded
Agree
Funny
Helpful
Interesting
Thanks
Mortada Engineer
Saudi Arabia
Mortada
 

I've checked can as instructions on extraordinary website above mentioned, resistance of EPS control module is not as specified. No reading on multimeter.

0
Ð Awarded
Wissam Owner/Technician
Lebanon
Wissam
 

Hello ahmad i faced this problem you should change power steering with new one

+1
Ð Awarded
Helpful
Mortada Engineer
Saudi Arabia
Mortada
 

Thanks dear sir Power Steering with EPS control module or just EPS ?

0
Ð Awarded
Mortada Engineer
Saudi Arabia
Mortada
   

Thank you dear sir Customer has replaced two power steering and one EPS control module second hand, and I've tried to connect two EPS control module second hand with the harness of it, the main problem that PCM and Dashboard losing communication with EPS control module U0131.

0
Ð Awarded
Glenn Owner/Technician
Texas
Glenn
 

Is this supposed to read 120 Ohms? Usually that suggests a bad resistor on one of the modules affected.

+1
Ð Awarded
Agree
Mortada Engineer
Saudi Arabia
Mortada
 

Thanks dear sir Is't 55-65 ohms ?

0
Ð Awarded
Tarsis Mobile Technician
Curaçao
Tarsis
 

Hi sir,I can see that you have a full crash event . Please if it possible check the front wiring harness at the radiator frame. There can be broken wires, if not it will be better to change the power steering .

+1
Ð Awarded
Thanks
Mortada Engineer
Saudi Arabia
Mortada
 

Resistance of can hi and low of Dashboard pin no 10 and 22 also pin 12 and pin 24 are 120 ohms consecutively.

0
Ð Awarded
Eric Owner/Technician
Wisconsin
Eric
 

Our Mazda 6 vehicles didn't get Electronic Power Steering until 2014, so I'm not sure how much different your vehicle will be from what I'm used to. Looking at the wiring diagrams you provided, it looks like there is a problem with the High Speed CAN. If you measured 120 ohms resistance across the CAN lines then you have an open circuit somewhere in the CAN lines. The correct measurement should…

0
Ð Awarded
Mortada Engineer
Saudi Arabia
Mortada Update
 

I've checked with tester : BCM : U0401:68-28 invalid Data Recieved From ECM/PCM A U0131:16-0A lost communication with power steering Control Module A U0415:92-08 invalid Data Recieved from anti-Lock Brake System(ABS) Control Module A PCM U0131:00-AF lost communication with power steering Control Module A RCM : Codes mentioned in report attached here today sep. 25 2021

0
Update Ð Awarded
Timothy Owner/Technician
Wisconsin
Timothy
 

Mortada, As others have stated, you need to have approx. 60 ohms resistance for the CAN lines across pins 14/6 at the DLC. That value would show a complete circuit across the entire high-speed CAN. If you've got 120 ohms when all modules are connected, you've an open on the CAN lines. You need to solve that first…

+1
Ð Awarded
Agree
Helpful
Mortada Engineer
Saudi Arabia
Mortada
 

Dear sir, Thank you, I've connected all of the modules and any other high speed CAN connectors I've disconnected before. Resistance measurement across terminals #14 and #6 : 61.5 ohms.

0
Ð Awarded
Mortada Engineer
Saudi Arabia
Mortada
 

Dear sir, Thank you, I've connected all of the modules and any other high speed CAN connectors I've disconnected before. Resistance measurement across terminals #14 and #6 : 61.5 ohms. Reply Edit

0
Ð Awarded
Eric Owner/Technician
Wisconsin
Eric
 

Mortada, I'm not sure your understand the testing process. Most high speed CAN systems in use today use two terminating resistors, each measuring 120 ohms. The two resistors combined in the high speed CAN circuit give you a measurement of 60 ohms when measuring across the high speed CAN high and low circuits. From the testing results you have posted, it appears you are measuring individual…

+1
Ð Awarded
Helpful
Thanks
Mortada Engineer
Saudi Arabia
Mortada
 

Dear sir, Thank you, I've connected all of the modules and any other high speed CAN connectors I've disconnected before. Resistance measurement across terminals #14 and #6 : 61.5 ohms. Attached here phot for measurement result.

0
Ð Awarded
Eric Owner/Technician
Wisconsin
Eric
 

I took some time and went through the wiring diagrams you supplied. They are difficult to follow and a lot depends on the options the vehicle has. Without knowing the vehicle options or having a better wiring diagram the only thing I can suggest at this time is to monitor the high speed CAN with a lab scope. Since the ABS and EPS modules are the ones that are seen as missing or sending invalid…

+1
Ð Awarded
Thanks
Timothy Owner/Technician
Wisconsin
Timothy
 

OK, that basically means that the basic CAN circuit is most likely not completely broken. But, you've got to remember that you can have just a few strands making the connection and still measure OK. Check the voltage at those same pins with the KO or engine running, should have around 2.5V, measured to ground, and fluctuating, both above and below those voltages by a little bit. If you measure…

0
Ð Awarded
Mortada Engineer
Saudi Arabia
Mortada
 

Thank You dear sir, the voltage at those same pins with the KO or engine running are 2.20 V and 2.67 V between Red and GND and Green and GND, Customer has tried EPS and EPS control module from second hand, but the same problem.

0
Ð Awarded
Mortada Engineer
Saudi Arabia
Mortada
   

I've checked the CAN voltages at the EPS. They're the same as at the DLC, then the lines are up and the EPS has an issue…as You've stated before dear sir.

0
Ð Awarded
Glenn Owner/Technician
Texas
Glenn
 

Have you tested the torque sensor? If it is not providing an input, the EPS will not work.

+1
Ð Awarded
Thanks
Mortada Engineer
Saudi Arabia
Mortada
 

Please, how to test the torque sensor?

0
Ð Awarded
Mortada Diagnostician
Saudi Arabia
Mortada Delay
 

Customer has took his vehicle without repair, because I told him to order Steering Control Unit and steering assembly, he report that he has replaced them as the second hand but the same issue.

0
Delay Ð Awarded