DEF Sensor Fault codes on 2017 Allegro Bus AP 40- ISL 450

[Redsoxfan1]

I have about had it with my Rig, from Loss of power issues, to failed slides and warranty service back Tiffin. Seems like things are failing constantly.. Sorry I am venting but I really need some advice.

Today we started our rig to head out on a 7 day trip to Yosemite and BAM... Check Engine light and MIL warning are on the dash. There are Two Error codes on the registry pointing toward the ECM with sensors faults.
I called Tiffin and was told the DEF head had to be replaced which has the Temp and Level senors connected.
The rub is that the Rig will go into shut down if the codes are in the net work
or ECM. Great! Good thing I wan't going over a Mountain!

Anyone had this same issue?
The factory is sending the new DEF head. I will do the work rather than wait months of a service center window.

A few factoids>
I noticed the sensor has some deposits on the senor rod by looking through the fill port. The tank has 3/4 of DEF. The in Northern CA is around 70 f.
To pull the head I will have to pull the side panel to get the DEF tank out to replace this part.
Wish me luck,

[Lt Dan]

This is a known issue with some 2017-2018 Power Glide chassis coaches. There have been several noted failures of the DEF system, which is not Tiffin's doing but a bad batch of DEF tank heads from the manufacturer. I have been sweating ours going out.

[Redsoxfan1]

Originally Posted by Lt Dan

This is a known issue with some 2017-2018 Power Glide chassis coaches. There have been several noted failures of the DEF system, which is not Tiffin's doing but a bad batch of DEF tank heads from the manufacturer. I have been sweating ours going out.

Thanks for your reply, are you running with the with codes?

[RWDJR.]

Look under the Freightliner Chassis section under DEF inconsistencies. Had the same problem, replaced the DEF head and reprogrammed the ECU and everything seems right. Run 2k, and another 1200 this spring with no problems.

[RWDJR.]

Originally Posted by Lt Dan

This is a known issue with some 2017-2018 Power Glide chassis coaches. There have been several noted failures of the DEF system, which is not Tiffin's doing but a bad batch of DEF tank heads from the manufacturer. I have been sweating ours going out.

The DEF Head is under the Cummins Warranty.

[RWDJR.]

Originally Posted by Redsoxfan1

I have about had it with my Rig, from Loss of power issues, to failed slides and warranty service back Tiffin. Seems like things are failing constantly.. Sorry I am venting but I really need some advice.



Today we started our rig to head out on a 7 day trip to Yosemite and BAM... Check Engine light and MIL warning are on the dash. There are Two Error codes on the registry pointing toward the ECM with sensors faults.

I called Tiffin and was told the DEF head had to be replaced which has the Temp and Level senors connected.

The rub is that the Rig will go into shut down if the codes are in the net work

or ECM. Great! Good thing I wan't going over a Mountain!



Anyone had this same issue?

The factory is sending the new DEF head. I will do the work rather than wait months of a service center window.



A few factoids>

I noticed the sensor has some deposits on the senor rod by looking through the fill port. The tank has 3/4 of DEF. The in Northern CA is around 70 f.

To pull the head I will have to pull the side panel to get the DEF tank out to replace this part.

Wish me luck,

It’s 100% covered under the Cummins Warranty. Let a Freightliner or Cummins Garage do the work.

[garykk]

Originally Posted by RWDJR.

It’s 100% covered under the Cummins Warranty. Let a Freightliner or Cummins Garage do the work.

Umm, I don’t think so. From what I have read, the problem is Tiffin’s. Cummins does not supply the def unit on a Powerglide chassis.

[RWDJR.]

The DEF head has to communicate with the Cummins ECM. Wouldn’t know why Tiffin would do that.

[Redsoxfan1]

Correct, It's a Tiffin Issue and changing the Head got me going..
Thx for the reply!
joe

[mrschwarz]

I had the same issue and Tiffin, not Cummins fixed it under warranty.

[garykk]

Originally Posted by RWDJR.

The DEF head has to communicate with the Cummins ECM. Wouldn’t know why Tiffin would do that.

On the Powerglide chassis, Tiffin supplies the DEF tank and accompanying sensors.

[RWDJR.]

Originally Posted by garykk

On the Powerglide chassis, Tiffin supplies the DEF tank and accompanying sensors.

I do see that now...........

[Outbumn]

Second time in 2 months I got the following fault codes:
3216-9 Aftertreatment 1 Intake NOx Sensor - Abnormal Update Rate

3031-9 Aftertreatment 1 Diesel Exhaust Fluid Tank Temperature - Abnormal Update Rate

Took it to Cummins last month, they could not find anything wrong and cleared the codes.

Guess I will call Tiffin service this time.

Are these the same codes everyone else is getting?

[garykk]

Originally Posted by Outbumn

Second time in 2 months I got the following fault codes:
3216-9 Aftertreatment 1 Intake NOx Sensor - Abnormal Update Rate

3031-9 Aftertreatment 1 Diesel Exhaust Fluid Tank Temperature - Abnormal Update Rate

Took it to Cummins last month, they could not find anything wrong and cleared the codes.

Guess I will call Tiffin service this time.

Are these the same codes everyone else is getting?

I was repeatedly getting some of those same codes. Spent over 45 days at repair shops. Finally contacted Gary Harris and his engineers figured out it was a relay in the chassis battery compartment, replaced the relay and tightened a couple of wire crimps and problem solved ..