ABS Light w/ Staggered Wheels (Same Diameter)

[NorCal_03Cobra]

Been having an issue with the ABS light being on and I would appreciate some input from others to resolve it. I've looked into a number of threads and it seems that having +/- 5% variance in wheel height is allowable before the ABS light is triggered.

Front = 17x9 275/40/17 Nitto NT555
Rear = 17x10.5 315/35/17 Nitto NT05

According to this calculator I have the following:


Size / Diameter / Width / Sidewall / Circum / Revs/mi
275/40/17 = 25.7 / 10.83 / 4.33 / 80.6 / 786.3
315/35/17 = 25.7 / 12.4 / 4.34 / 80.6 / 785.7


With the information above I would think that I am within a close enough tolerance to avoid an ABS error. One thing that comes to mind is to check my tire pressure (although I don't think that would create a large enough discrepancy to trigger the error) and lastly to check the ABS sensor for failure. From what I recall before switching to the 10.5 rear, there was no problem with the ABS sensor/light.

There are no DTCs present and everything seems to be working fine - with the exception of the ABS system I suppose. Is there anything potentially in the tune that could be affecting this?

What am I missing here??

 

[Skitzerman]

There is not enough variance in front to rear diameter and rev's per mile to cause the ABS light to come on. Check all your connections. Your ABS Module may be going out too. I have a one inch difference in front to rear diameter and significant rev's per mile difference. I did make the appropriate changes in the tune to compensate for it.

 

[bubblehead93]

Not all readers read ABS codes... do you know if yours does... airbags, ABS, wheel sensors, etc...

r/
Andy

 

[NorCal_03Cobra]

Thanks for your replies.

I do not know if I have enough diagnostic tools to check those items. I have the SCT X3 handheld and I do have the SCT PRP software, but I do not know if that would provide enough insight check those items you suggested.

I have a mechanic buddy who has a more advanced diagnostic code reader which might be what I need. I assume the appropriate tool would tell me if its left or right hand side that is failing?

Anyone have the part number for the ABS sensor(s)? I found the following on LateModelResto:

99-04 LH Rear @ $64.99
99-04 RH Rear @ $64.99

 

[Skitzerman]

Before you start throwing money at it, get someone to diagnose the problem and narrow it down. You might have an open circuit or a faulty module.

 

[bubblehead93]

completely agree, get some one to read the ABS codes, could be anything from a faulty ABS module to dirty/bad sensors... not a system you want to easter egg your way through by replacing parts and seeing if it fixes the problem, besides you will need to clear the ABS fault codes once you fix the problem...

r/
Andy

 

[stangfreak]

I have the same combo and no abs light. Noway that is causing your issue.

 

[NorCal_03Cobra]

Got in touch with my mechanic buddy and he has an advanced diagnostic tool to read ABS codes. Going to see what comes up there before spending any money.

Car is currently about 71k miles so I'm guessing there will be other issues coming up in the future as well. I want to remember seeing a thread for maintenance/replacement part timeline (i.e. estimated time for part failure) - does this sound familiar to anyone?

 

[Skitzerman]

Terminator FAQs

http://www.stangshiftergaskets.com/2003_2004faqs.htm

 

[BlckBox04]

I have the same exact set up. There's no way those wheels are causing the light to come on. Maybe the ring got knocked off somehow or it's something else.

 

[NorCal_03Cobra]

Terminator FAQs

http://www.stangshiftergaskets.com/2003_2004faqs.htm

Hmm... I'm familiar with Bob's FAQ, but thats not quite what I had in mind for what I want to remember seeing. I swear there was a thread around documenting/estimating part failure timeline (e.g. intercooler pump fails after 50k miles, how long OEM alternator is good for, etc etc...)

From everyone's responses it definitely seems to be an ABS sensor/computer error and not the wheel combination. I'm going to see about hopefully meeting up with my buddy this weekend and using his advanced diagnostic handheld tool.

 

[NorCal_03Cobra]

Well I finally met up with my mechanic buddy and used his 'Genisys EVO' OBD2 diagnostic tool which gave me the following codes:

I had previously planned to do 'The Big 3 Upgrade' and with the 'Battery Voltage Low' code I figured this would be a great time to do it. Here is a picture of the OEM ground strap that runs from the drivers side engine mount (above oil filter) to the frame and the KnuKonceptz Kolossus Flex Kable 0 Gauge OFC (oxygen free copper) -- I have never seen anything like it before, it is super flexible and has some serious weight! Here is a comparison of the OEM ground strap vs the Knuconceptz 0 gauge (ring terminals were soldered on with a propane torch, taped, etc etc...):




The ABS light is still on, but the car feels a little more responsive under throttle (maybe a placebo effect?)... Anyways, the ABS light is still on and I've checked all of my fuses - both Battery Junction Box and Central Junction Box (under dash).

I couldn't find anything online for the fuse diagrams, so I pulled out my wiring diagram book and snapped a couple of pictures for anyone that needs the info -- here are the diagrams for both BJB and CJB: http://imgur.com/a/bs5X8

I guess the next thing I'm going to do is see about getting a new battery as the Optima Yellow I have is probably 7-8 years old and likely due for replacement. After that I will probably install the 60# injectors and BA2600 I've been sitting on for a while and get a solid tune from Don @ LaSota Racing as I have yet to do my own tune with the SCT PRP... Thereafter, I guess I'll have to see about this U1262 'Comuniction Protocol Comumiction Bus Malfunction' code and maybe replace some sensors or something...

Also, these images are frickin' huge on my end and I couldn't figure out how to resize them using the HTML/BB code - sorry!