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ABS fault codes in Scan Tool but no ABS lights on

13K views 21 replies 9 participants last post by  u1arunit 
#1 ·
Whats up everyone, was hoping to seek some insight on a couple of codes my cheap obd2 scanner are finding. See them below. They sound semi important but whats strange is I would think there would be a ABS light on for this one. All signs point to ABS and brakes. I wonder if these modules were unplugged at one time when the ignition was turned on perhaps? I have the option to clear the codes in my scanner but they don't go away. As far as fuses go I did check the driver side fuse panel (No ABS fuses in there) Also checked the big fusable link box and nothing I see associated with ABS in there as well.

Looking for some advice on this one.


Here were the codes.

C1140-00 - Fault in ABS Actuator/ Relay


U1000-01:

The trouble code U1000 is a vehicle specific code primarily found on Chevrolet, GMC and Nissan vehicles. It refers to a "Class 2 communications failure." Generally, this code will precede an additional code that identifies the module or area of the failure. The second code may be generic or vehicle specific.

Read more at: https://www.obd-codes.com/u1000
Copyright OBD-Codes.com
 
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#2 ·
First it really helps if you let us know what model of Q50 you have, there is 2 generations of car and there is typically
seperate ABS systems for RWD and AWD cars so it's important to give us your basic information. Hah

Look at the SM a U1000-01 code it appears to be a generic communication error, if your able
to clear the Code on your scan tool do so and see if it comes back.

If not you'll need to bring the car in and have the connections inspected and or possibly the Control Module replaced.
I don't recommend you attempt replacement yourself as it appears to require a CONSULT tool and a backup/export of your configurations
before the old unit it removed.
 

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#4 ·
Definitely would help if the OP as well as everyone else here put relevant car information in their signature (year, model, options, mods) in order for us to assist in answering questions.

It doesn't appear to me that there are separate ABS systems for RWD and AWD. The FSM shows only one for both.

The C1140 DTC is indicating there is/was a malfunction detected in the actuator relay in the ABS actuator and electric control unit. That DTC can be classified as PAST or CRNT. This is determined with a CONSULT scan tool. If after running the DTC confirmation procedure, the CONSULT displays PAST, then the DTC is cleared and no further action is necessary as it was a temporary problem. If CRNT is displayed then the problem still exists and could be due to:

Faulty or loose harness or connector
ABS actuator and electric control unit
ABS actuator and electric control unit power supply system
Fuse
Fusible link
Battery

There are fusible links for the ABS actuator and electric control unit in the Fuse and Fusible Link Box. They are: Fusible Link "L" 30A and Fusible Link "N" 50A. I don't think that's the problem though and I doubt it's the battery either. See diagram below:



If the fusible links are ok, then the ABS actuator and electric control unit's power supply and ground circuit need to be checked as well as the pin terminals on the harness connectors. If there's no problem there then it's likely the ABS actuator and electric control unit needs to be replaced.

Don't muck around with the ABS system. This is not shadetree mechanic work and brake control system maintenance should be left to qualified mechanics. It requires a CONSULT scan tool that the service department uses for diagnostic purposes. You can inspect the connectors for something obvious but I doubt you'll find anything. The ABS actuator and electric control unit is located on the right next to the brake fluid reservoir and master cylinder. See diagram below (#12):



The U1000 DTC indicates that that there was a communication interruption in the CAN gateway of greater than 2 seconds. This could have been temporary or it is indicating a reoccurring communication problem in the CAN highway if it doesn't clear with an ignition cycle. Again, a CONSULT scan tool is necessary to properly diagnose the problem.
 
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#5 ·
As per Avedis notes below the location appears to be below the Brake Reservoir, CONSULT is a dealer level scan tool that provides a staggering amount of
control over a car as well as the ability to monitor and report on nearly every sensor.

This is definitely work for a certified technician so just visually confirm that the cables are seated correctly, please don't disconnect anything.
Your model is a 2014 so as long as you're mileage isn't very high you should be covered under warranty on the car.

Definitely would help if the OP as well as everyone else here put relevant car information in their signature (year, model, options, mods) in order for us to assist in answering questions.

It doesn't appear to me that there are separate ABS systems for RWD and AWD. The FSM shows only one for both.
I'll double check the SM later , it was a chart covering the various components and differences based on trim levels I admittedly was just passing through
that section however.
 
#6 ·
Thanks everyone, after reading all this and referring to the SM I'm hoping there was just a past ABS issue and the codes are stored and my cheap scan tool just can't clear them or decipher CRNT or PAST. Learned a few new things too!
 
#7 ·
No problem sir, your local car shop can loan you a decent scan tool that is able to clear the codes and for free usually. Scotty Kilmer actually just did a video on this topic with a G37, I think his content
is pretty hit or miss but this was one of his better pieces of content.

https://youtu.be/PwfYcr-j27k?t=110
 
#9 ·
Just curious...what Scan Tools is anyone using that you are very happy with and gives a professional amount of data like Scotty's but isn't $2000:eek:

:)
 
#12 ·
Aside from JB4, I use Bluedriver. Support people respond quickly and with some level of honesty - like how they said certain mazda models are more prioritized than nissan (vr30).
 
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#10 ·
EcuTec tune has code reading and clearing ability. Under $2000 and you get the other goodies!!??
 
#11 ·
What are your thoughts on BlueDriver?
 
#16 ·
I've not used it myself but I have heard a few people confirm it's good performance/value, I however would recommend stepping up to the below model
it's actually one Scotty recommended as a good middle-ground unit in another video.

https://www.amazon.com/dp/B01HNO5PLY/ref=psdc_15707381_t2_B00BGH0EAC

I'm tired and sweaty watching that video, LOL.... but I want that scan tool.
Hah it's why I do most of my car video watching with beer in hand. ;)
I'd love to have it myself $2,000 is a lot of money to throw down on a tool (Read as Toy) I may use a few times a year. Hah
 
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#13 ·
If you want full diagnostic capability and programming for Nissan and Infiniti vehicles, then you might consider this:

Nissan Consult-3 III Plus Nissan Diagnostic Tool Support Programming - $550

You'll need a laptop also.
 
#21 ·
I bought the BlueDriver off Amazon...supposed to arrive tomorrow. I'll play with it and decide if worth keeping. I am looking at the Launch CRP123 too...not bad pricing but finding for closer to $100 on eBay versus Amazon.
 
#22 ·
I have the BlueDriver unit and it works well for the price when I don't have my Snap On scanner with me.
 
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