Parking Sensors wont turn On 2020 1500 DT

[20BTSHemi]

I've been looking for an answer on this to no avail so far, out of nowhere, my parking sensor buttons stay illuminated indicating the sensors are "Off" has anyone dealt with this and if so, what's the fix/reset?

*68° F and dry conditions* No rain, no snow, ice, etc.

TIA

 

[SD Rebel]

Check the F49 (SNSR Blind Spot) on the internal fuse panel in the dash. Otherwise it could be a sensor issue, this may require a trip to the dealer or someone with a good Mopar scanner.

 

[skyhawk42]

Did you change tire size in Alfa? I hear the park sensors won’t work if you go over a certain size. Not sure the size, but I remember it was metric just shy of a 35” that caused it to stop

 

[Malodave]

I drove for about 4 Months with my Rear Parking Sensors not working.

Well, after spending 10 Hours at the Dealer's Service Department. My Rear Parking Sensors are working again.
They found a Software Update for them. STAR Case 102062370. Go in for what should have been minor fixes
and Stay there all day.

Malodave

 

[20BTSHemi]

Did you change tire size in Alfa? I hear the park sensors won’t work if you go over a certain size. Not sure the size, but I remember it was metric just shy of a 35” that caused it to stop

I sure did.. Dealer put in size of tires to ECM to calibrate speedo..

 

[skyhawk42]

Do you have Alfa? Try lowering the size a bit and the park sensors will work again. I know there is a number you can go up to and still have the park sensors working, but it is lower than a true 35” so it reads off by 2 mph or so

 

[skyhawk42]

2557mm is max size with park sensors still working

 

[Idahoktm]

2557mm is max size with park sensors still working

Not true. I used 2625 mm's for my 305/55x20 tires and my sensors still work.

 

[20BTSHemi]

I have 285/65/20 Tires, so it comes out to like a 34.5" measurement, It does seem like whatever the Dealer did to calibrate my speedo has caused this though

 

[skyhawk42]

Not true. I used 2625 mm's for my 305/55x20 tires and my sensors still work.

My buddy did his and went back and forth and that’s what he said was the highest setting that he found to work.

 

[TXECOD]

I had the dealer calibrate mine for 34.5 inch tires and the park sensors haven't worked since. They told me they contacted RAM and opened a star case. The answer came back that they were aware of the issue, and that it was caused by a software glitch, but that since this issue is only effecting less than 200 vehicles nationwide that it would be cost prohibited to fix it and they have no plans to fix it. I explained that the $75k truck I bought was cost prohibited and that I wont be buying another.

 

[skyhawk42]

I doubt less than 200 trucks nation wide are affected. There’s probably more than that on this forum in a given day that are affected. Having a full size pickup with 35s is a very common thing. I for sure would love my speedometer to be accurate AND keep my factory equipped parking sensors working. Maybe we need to take a poll on here and see how many have larger tires and would like to see this addressed

 

[Idahoktm]

I had the dealer calibrate mine for 34.5 inch tires and the park sensors haven't worked since. They told me they contacted RAM and opened a star case. The answer came back that they were aware of the issue, and that it was caused by a software glitch, but that since this issue is only effecting less than 200 vehicles nationwide that it would be cost prohibited to fix it and they have no plans to fix it. I explained that the $75k truck I bought was cost prohibited and that I wont be buying another.

This is not Ram's fault, it's yours. You put 34.5" tires on the truck and asked them to recalibrate the speedometer. They did that. If you want the sensors to work, recalibrate for 34" tires and the sensors will work again.

 

[jimothy]

Not true. I used 2625 mm's for my 305/55x20 tires and my sensors still work.

2557mm is max size with park sensors still working

Those work out to 100.6” and 103.3” tires…any rubbing?

Edit: Ah, I see. Circumference not diameter. You can definitely go higher than 2625mm; that’s only 32.9” diameter. I’ve used TazerDT (which lists the diameter in inches) to go to whichever value was closest to 34.6”, and my sensors work. That’s about 2,760mm circumference.

 

[TXECOD]

This is not Ram's fault, it's yours. You put 34.5" tires on the truck and asked them to recalibrate the speedometer. They did that. If you want the sensors to work, recalibrate for 34" tires and the sensors will work again.

Thanks for the great contribution to this thread. I'm fully aware that I asked for them to calibrate my speedometer. I'd gladly pay for them to put it back. I work for the f'ing dealer in question. I'm the parts manager, and for the last year all I can get from the service department is "we have tried to recalibrate it back to the original size, but can't, and Star says it can't be done. "

 

[skyhawk42]

So I was thinking about this again. If the truck needs to see a stock size, the largest size would be from a TRX right? I google searched that tire size and it shows 325/65 r18 with 108.6” or 2760mm. That would mean that the 34.6” that was mentioned above would be the largest size that would work. Anyone want to chime in on this thought?

 

[Idahoktm]

Thanks for the great contribution to this thread. I'm fully aware that I asked for them to calibrate my speedometer. I'd gladly pay for them to put it back. I work for the f'ing dealer in question. I'm the parts manager, and for the last year all I can get from the service department is "we have tried to recalibrate it back to the original size, but can't, and Star says it can't be done. "

You're lucky that your dealer offered to calibrate your speedometer. Most won't do it and based on your reaction, I can see why.

Buy AlfaOBD and do your own calibration. You don't need to go back to the stock size. I can't remember the maximum, but it's right around 34". At 34", your speedometer will be pretty accurate.There's a long AlfaOBD thread with that info.

 

[TXECOD]

You're lucky that your dealer offered to calibrate your speedometer. Most won't do it and based on your reaction, I can see why.

Buy AlfaOBD and do your own calibration. You don't need to go back to the stock size. I can't remember the maximum, but it's right around 34". At 34", your speedometer will be pretty accurate.There's a long AlfaOBD thread with that info.

Could you please point me in the right direction of where to purchase the AlfaOBD ?

 

[skyhawk42]

AlfaOBD.com download software there and on the home page it lists some of the possible OBD adapters and secure gateway bypass that you will also need. I bought mine on Amazon. I have the mx+ and a gateway bypass made by ecri

 

[Malodave]

Just had my Rear Parking Sensors go out again and the Camera System with them.

I am trying a hard reset by disconnecting the Battery.

Malodave