Freightliner Dash problem, intermittent low air and start

[rlbarkleyii]

I run a 02 Winnebago 32" with Freightliner XC chassis, powered by Cummins 5.9 ISB engine. Sitting stationary engine off in parking lot when storm blew up for maybe thirty minutes. after storm I started engine and it built air ti 120psi, with front tank at 130, the rear tank fell to sixty and low air buzzer sounded. checked outside, no air leak, maxi-brakes released. Turned engine off to see if that would reset gauges, tried to restart engine would not crank. retried starting several times, finally restarted. drove back to home base uneventful. when i reached home turned off engine and she fired right up. Called Freightliner 24/7 and the tech told me it sounded like dash light strip was bad, might need to be replaced. The start issue had not occured at that point and was not discussed.

QUESTION: does the dash light strip have anything to do with engine starting? If light bar is defective, could it prevent engine from starting?

Any information that is given is appreciated.

[dickandlois]

2 hours ago, rlbarkleyii said:

I run a 02 Winnebago 32" with Freightliner XC chassis, powered by Cummins 5.9 ISB engine. Sitting stationary engine off in parking lot when storm blew up for maybe thirty minutes. after storm I started engine and it built air ti 120psi, with front tank at 130, the rear tank fell to sixty and low air buzzer sounded. checked outside, no air leak, maxi-brakes released. Turned engine off to see if that would reset gauges, tried to restart engine would not crank. retried starting several times, finally restarted. drove back to home base uneventful. when i reached home turned off engine and she fired right up. Called Freightliner 24/7 and the tech told me it sounded like dash light strip was bad, might need to be replaced. The start issue had not occured at that point and was not discussed.

QUESTION: does the dash light strip have anything to do with engine starting? If light bar is defective, could it prevent engine from starting?

Any information that is given is appreciated.

the rear tank fell to sixty and low air buzzer sounded .How Long did the coach set before the low pressure alarm went off?

tried to restart engine would not crank. There is a large 100 to 120 amp auto reset fuse real close to the starter - it supplies power to all the 12 volt circuits for the dash and starter circuit.

      This could be an issue where the plastic enclosure of the circuit breaker has cracked and exposed the internal circuit to water.  Have seen this problem first hand

. This problem would also disable the dash light bar. 

The time line between the air pressure level peak and the alarm could offer a clue to that issue.

   Why did it startup at all! question is how much water built up under the coach during the rain burst? Did the cooling fan move a quantity of water into a damaged fuse?

After you got the engine running , did the dash lights work along with the light Bar?

Did the air pressure alarm come on again at home base?

Rich.

[richard5933]

A bad ground or a loose connection can cause all sorts of problems like this. Is the light strip in a location you can access to check to see if something has come loose?

[jleamont]

Rlbarkley, welcome back! I was thinking of you the other day, hadn’t seen you on here in a while.

Your concern definitely sounds like water intrusion. DandL’s troubleshooting above would be where I’d start.

[rlbarkleyii]

On 5/19/2019 at 8:23 AM, jleamont said:

Rlbarkley, welcome back! I was thinking of you the other day, hadn’t seen you on here in a while.

Your concern definitely sounds like water intrusion. DandL’s troubleshooting above would be where I’d start.

Greetings; Nice to know you have been missed. Been sidelined for the last year. I am now a caregiver for the DW, unable to get too far from home.

[rlbarkleyii]

On 5/19/2019 at 12:21 AM, DickandLois said:

the rear tank fell to sixty and low air buzzer sounded .How Long did the coach set before the low pressure alarm went off?

Response: The engine was running when the low air went off.  i had been driving for a hour in dry weather. Parked and shut down engine. It started to rain and i sat there for a hour or so, storm came up and lasted about 30 minutes. Started engine to leave and started normally, when air built up to 120psi i released park brakes. immediately rear tank guage dove down to 60 # +-.  like the guage lost power. Within seconds the guage went back and forth between 60 and 120 more than one. I shut off engine thinking i would reset the guage and the it would not start. Tried several times, finally it started again. Drove home without incident, however guage did bottom again several times. 

ot crank. There is a large 100 to 120 amp auto reset fuse real close to the starter - it supplies power to all the 12 volt circuits for the dash and starter circuit.

      This could be an issue where the plastic enclosure of the circuit breaker has cracked and exposed the internal circuit to water.  Have seen this problem first hand

. This problem would also disable the dash light bar. 

Response: I am familiar with the circuit breaker you are referring to,  several years ago it shut me down at a traffic light when a wire was corroded. Mine does not have a plastic cover and is exposed to road debris and moisture in the air stream. I will be checking the wiring and clean it up again. It would be helpful if you could post a picture of plastic cover.

The time line between the air pressure level peak and the alarm could offer a clue to that issue.

   Why did it startup at all! question is how much water built up under the coach during the rain burst? Did the cooling fan move a quantity of water into a damaged fuse?

Responce: Time between 120 and 60 reading was maybe a second, it was clear the the guage was responding to a electrical problem, not the actual air level.

On 5/19/2019 at 12:21 AM, DickandLois said:

After you got the engine running , did the dash lights work along with the light Bar?

Did the air pressure alarm come on again at home base?

Response: After the engine was running the light strip appeared normal, but the guage bottomed a couple of times on the way home. The very next day, (dry, hot, weather) the same thing happened a couple of times. I shut down the engine and after a couple of hours i tried to start it and it would not start. The dash went through its normal sequence but would not crank. After trying a dozen more times, while calling a tow truck, alas it started. when i got home, i shut it down and it restarted, over and over. Go Figure????

 

Rich.

 

[dickandlois]

rbarkley,   Looked and could not find a picture of the relay in my computer picture files. Maybe it never got transferred from the camera SD card.

However ! what I was referring to was the plastic molded housing its self. there are tabs molded on each end that are used to mount the unit to the chassis. The cables have rubber boots that protect the cable connection points. 

The starting issue could be the castle ignition relay - small relay mounted close to and supplies starting current to the starter.

           but the guage bottomed a couple of times on the way home

The rapid drop in air pressure sounds like a cold solder joint in the VDU module. Never goes between 120 and 0 ?  drops from 120 to 60 psi. Do both gauges drop or just One?

 

Rich.

 

[richard5933]

Do these engines use an air control to shut down the engine? The problem immediately restarting may be connected to the air pressure problem if air controls are used. I know that these newer engines largely use electronic controls and not mechanical controls like mine, but I wonder if the trouble restarting was connected to the system getting the low air pressure error message?

Just had a thought that may or may not help...

Pressure never dropped below 60psi - had it dropped too much further the brakes should have self-applied. I'm not sure of the exact tank layout on this coach, but there will probably be a tank for application of the emergency braking system which is somewhat isolated from the rest of the system with a check valve of some type. Sounds like the dash monitor is reading the pressure forward of that. If this is the case, then I'd be looking for a problem with the system forward of that point, including any air lines which may leak when the suspension goes through its movement. There may be a line being pulled/pinched when the suspension moves to an extreme position.

 

[jleamont]

3 hours ago, DickandLois said:

rbarkley,   Looked and could not find a picture of the relay in my computer picture files. Maybe it never got transferred from the camera SD card.

However ! what I was referring to was the plastic molded housing its self. there are tabs molded on each end that are used to mount the unit to the chassis. The cables have rubber boots that protect the cable connection points. 

The starting issue could be the castle ignition relay - small relay mounted close to and supplies starting current to the starter.

           but the guage bottomed a couple of times on the way home

The rapid drop in air pressure sounds like a cold solder joint in the VDU module. Never goes between 120 and 0 ?  drops from 120 to 60 psi. Do both gauges drop or just One?

 

Rich.

 

Rich, this issue was also an problem on Monaco coaches built by Navistar. They must use the same manufacture for the components as Freightliner, sadly it carried into their truck line also 

On those the situation would be scary, they didn't drop fast enough for you to think is wasn't an air leak, they would drift down slowly, sound the alarm, you pull over thinking the parking brake was going to be applied and nothing happens. Shut it off, restart it and the gauges were back to normal. 

[rlbarkleyii]

The front air guage remained normal throughout, the rear guage dropped to 60+- never below. Dropped faster than the air could leak, believe it to be electrical. Still don't get why the no start issue which never happened before.

[rlbarkleyii]

As a emergency measure I need to install a remote start switch in the rear electrical cabinet. Need some info, does the Winny Journey 02 start with a series parallel relay on 24VDC?  Anyone else ever did this?  Anyone know of diagrams for remote.?  Any coaches come stock or option with remote start near the engine compartment?

I have to do this because I will not be stuck somewhere because I cant start engine. Comments !!!

[wolfe10]

43 minutes ago, rlbarkleyii said:

As a emergency measure I need to install a remote start switch in the rear electrical cabinet. Need some info, does the Winny Journey 02 start with a series parallel relay on 24VDC?  Anyone else ever did this?  Anyone know of diagrams for remote.?  Any coaches come stock or option with remote start near the engine compartment?

I have to do this because I will not be stuck somewhere because I cant start engine. Comments !!!

Your coach, including starter are all 12 VDC-- no 24 VDC.

You already have a battery parallel/boost switch to allow house bank to augment chassis battery for starting the engine.

Yes, you could also add a remote start switch, but very few have done this  or found a need to do so.

[richard5933]

Almost every coach built on a bus chassis has rear compartment starting ability. Ours has a switch in the rear which sets either front or rear controls - both are not possible at the same time to prevent accidents. Not sure if something like that is possible or desirable in your application. The start button on the rear of ours runs parallel to the momentary switch at the front which engages the start system relay. If you have a wiring diagram for your chassis it should be pretty easy to wire a rear switch parallel to your front switch.

[dickandlois]

19 hours ago, rlbarkleyii said:

The front air guage remained normal throughout, the rear guage dropped to 60+- never below. Dropped faster than the air could leak, believe it to be electrical. Still don't get why the no start issue which never happened before.

This sure sounds like an electrical issue. You might call Winnebago and ask if your chassis has a VDU Air pressure Module and where it is located.

Second, These modules have had some poor solder issues. The common procedure is to replace them and they cost in excess of $1000.00.

     They can be repaired in most cases, but requires a person with very good solder skills and the ability to open the seal and do a good job of resealing the module.

The directions to repair are available. 

Rich.

 

[rlbarkleyii]

Current Status: Talked with Cummins Service Tech and Freightliner 24/7 Tech and I believe we have nailed down the cause which confirmed one or more of the suggestions given by board members. 

FIRST; The problem with the dash light bar, gauge and low air buzzer is one problem likely cause by the VDU  module as indicated earlier.To cure this problem I was told to remove the negative battery terminal of the crank battery's and leave them off for ten minuets or so. This would effectively reset the VDU module, and this is the only way it can be done. In the event that doesn't work, than the VDU is defective and must be ether repaired or replaced. I will be doing this reset  in the next few days, when I clean up my battery terminals and water the battery's.  If I have to repair or replace the VDU, I have sourced them out used for around $400 , new close to $1000. If I can't reset the VDU than I will remove the seal and attempt to solder the four connectors that most often fail. If that doesn't work i will likely by a used one.

SECOND:: The "no start"  engine condition is not related to the VDU or the light bar issue. The starter relay is found on the 02 Journey on the curb side rail mid-center on the engine. It is mounted to a bracket that projects it below the rail and consequently into the air and water stream when the vehicle is moving down the road, or the wind and rain is blowing under the unit. Both Cummins and Freightliner indicated that the position of this relay on earlier models and the other one on the drivers side (main 135AMP breaker for front end controls) have been problematic due to early failure from  corrosion and water. Both Freightliner and Winnebago have subsequently re-positioned the relay inside the nearby compartment, and or re-fabricated the bracket to keep it out of the air/water stream and tuck it away higher between the rail and the engine, depending on the year. I purchased a new one from a Cummins dealer and will  replace the relay and in the fall move it into the compartment. This will be a cheap fix, bought the relay for $23.00, the proper name for this part is "Relay Solenoid Magnetic", the White Rogers (MFG) and Freightliner part number is  ESX-120-105112-2

I'm optimistic that this will go well now that I have confirmed the cause and remedy, I will update this post after work is completed.