2008 Tahoe park assist codes short to battery

[jigfeett]

Make

Chevrolet

Model

Tahoe LTZ

Year

2008

Miles

200k

Engine

5.3

Just helping a friend. I have not looked at the car yet.
Active codes in park assist
B0958 B0959 B0960 B0961
parking aid rear sensor 1, 2 ,3 ,4 short to battery
They replaced all 4 sensors codes came back
They unplugged the module codes went inactive, then came back after clearing them.
Trouble shooting states.
1. check 8v term 1
2. check ground, low ref to ground less than 5ohm term 2
3. check signal to ground
4. check term 3 to v+ short to ground or open
5. if all good replace module
I think if all the sensors code up then they must be the wrong ones or the module is defective but how often do these modules become defective?
Are they a weak point?
Thanks

 

[nickb2]

how often do these modules become defective?

More often than four sensors going out at once. The odds on that are like winning the lottery. Would be good to know why someone would even change ALL four sensors if they have a bit of knowledge.

But at least we know all sensors are new, so after wiring is checked for integrity, only thing left would be the module. I do realize parking aid sensors are located in sweet spot for corrosion, I have had a few jeeps with ADAS on board from the states, they do not like the road salt. But 4 sensors at once go short to B+ or ground, wiring is first to jump to mind, then bad grounds causin high resistance, blew a driver or two in module/shorted out a transistor or two.

I see you have some form of getting flow charts, do you have access to OEM wirings? If not, post back, I will provide that.

 

[jigfeett]

Agreed don't know why they put in 4 except they must have bought as a group.
I do need an OEM diagram when you have time of course. My resources are limited just what ever I find on the google box. I had a lot of manuals and subscriptions but I left active wrenching years ago and now just help the kids and friends If I so choose..... It is good to choose...
I appreciate the help with these issues.
Thanks

 

[nickb2]

I found this nice, a TSB. See pdf.

I states to not replace ALL sensor and object module. But since they are all new, we will focus on what I said before, wiring. If that is THOROUGHLY checked out, then it is module time, and these need to be programmed if new, used, I don't know if they are vin matched, but I don't think so, but hey, you never know.

 

[nickb2]

Here is wiring. Also connector views. Again, pdf.

Hope this helps find the problem.

 

[jigfeett]

Thank you this information is much better than what I currently have. Does your information have connector view for the module connectors?
Thank you, I appreciate your help with this.

 

[jigfeett]

Update, went through all wiring, checked all sensors to for power and short to power + power to ground-and each other found nothing touching no issues.
I even went wire A to B from module to sensor no issues found.
I found that the module is obsolete and a replacement is offered,
When scanning, codes did not remain the same in the same scenario.
Switching sensor location made no difference.
Updates to follow.

 

[jigfeett]

Update I found a module at the wrecking yard, plugged it in and had vin mis match + some of same codes.

I have read that the aftermarket sensors are junk and may or may not work so I'll be doing some more checks.
I did the listen check and each sensor is clicking
I had the car in reverse and held a card board at each sensor and got the lights and warning buzzer for each one and that was one at a time.
The system is working just have the warning on the DIC, "service park assist"
I'm going to rescan and clear the codes then run it for a day then rescan to see what comes back.

I do not trust the after market sensors but they appear to be working.

I do not believe my scan tool to be defective but anything is possible.

Next step new module, I don't like throwing parts at it and will probably need dealer to program new unit.

 

[jigfeett]

Solved there never was a module issue.
I got random sensors from junk yard from 2013 chevy truck 2014 tahoe started with 2 active codes #3 & 4 short to battery.
Did a swap 1 & 4 coded up all 4 senors short to battery.
swapped out #4 with J Y sensor coded just sensor 3 short to battery.
swapped out # 3 with J Y sensor all codes gone.
Next day coded up with sensor # 2 short to battery.
At this point because I had a handfull of sensors I swapped # 1 & 2 with J Y sensors
Currently no codes but have miss matched color of sensor
Will get some T U paint to color the sensors, as thin as possible.
I'm calling this one done for now.....
Thanks again for the help.

 

[nickb2]

Will get some T U paint to color the sensors, as thin as possible.

Not recommended. And now, you have to calibrate if GM requires it. Or at the very least, test the system and see if a dynamic recal is available. If not, when using the park assist, it may not be within tolerances and code again in futur, or I foresee some scratched rims in the future when using the park assist.

Two cool sites to help with this, one is knowing full equipment on this truck, for this you go to vin decoder. https://vpic.nhtsa.dot.gov/decoder/

Next try autel site for adas coverage, type in what it asks for, it will show also if it needs calibration or not after sensor/multiple replacement.

http://www.maxisysadas.com/getCoverage.jspx

So, I did the work for you, on this year model, adas calibration was only available for autel in 2014up for canadian market.

Plz don't paint them, just leave them be. You will not be helping the JY sensors as the ultra sound will not like the touch up paint. There is special paint for that.

Here is a guideline I found for that. https://static.summitracing.com/global/images/chartsguides/b/bnm-9002-3003.pdf

 

[nickb2]

So I try typing dynamic adas calibration for your truck came up with this. If this would have been a caddy, same frame, would be a whole different story, but some gm's have different systems, hence the importance of using the vin decoder. Great free tool.

https://rts.i-car.com/collision-repair-news/typical-calibration-requirements-for-park-assist-sensors.html

Was this a concern on your truck I asked myself. Did mitchel thing, confirms my no paint an already painted sensor warning.



But no dynamic or static needed, confirms it only started later for your truck and/or does not support it. Just need to confirm with scan tool if all sensor are picking up ultrsound and if you paint them, you can actually see how reduced the sensor signal is on a scope.

 

[nickb2]

Some older models like this one will ask to do a "echo" test. I saw no mention of that, but to fine tune it, using objects and a scope could help. That way, you could compare readings from each sensor to know the amplitude of frequency is being respected on all sensors vs distance. Would suck to paint those sensors just to have to paint a new bumper later because painting the already painted sensors falsified the readings and what should have been a red warning was just a yellow warning etc.

Some ppl are just too stupid, rely on these systems to much and bump and scratch other stuff cuz the systems are out of calibration or just plain misaligned altogether.

 

[nickb2]

https://www.pepperl-fuchs.com/global/en/25518.htm

 

[jigfeett]

Thank you I'll leave them alone, I'll keep an eye out for more J Y sensors of similar color. there are e bay genuine GM part number ones out there that can be bought for a reasonable costs but they need to be color matched. The GM direct parts are excessive $100+ for one sensor.

I did do a test at 8 feet 4 feet and one foot for warning lights and sound and they all worked.
Thanks again until the next issue comes up.

 

[jigfeett]

update, 3 different junk yard sensors working with no issues, next job to tackle is replacing the rod for the rear gate automatcic opener, I do not know why it isn't installed it's just not there.