iRV2 Forums

iRV2 Forums (https://www.irv2.com/forums/)
-   Country Coach Owners Forum (https://www.irv2.com/forums/f112/)
-   -   ABS/ATC Light (https://www.irv2.com/forums/f112/abs-atc-light-493419.html)

gpounder 06-22-2020 10:00 AM

ABS/ATC Light
 
1 Attachment(s)
On my dash I have a blinking ATC light (automatic Traction Control).

I also have a ABS Blink Switch in the electrical bay (see picture). The blink switch has a green and orange led in it and it blinks a code. How it works is a mystery I hope someone can tell me. After random switch presses the ATC light on the dash will stay out for a while.

My questions:
1. In the production years 2006/2007 what brand ABS system did CC install?
2. Where is the control computer located?
3. Where is the module that controls the brakes located?
4. Where can I find a manual for my system?
5. Do you know the blink codes and sequences for the switch?
6. I know the differences between ABS and ATC so why do I get a ATC fail and not a ABS fail?

2-Nickels 05-25-2021 08:52 PM

Quote:

Originally Posted by gpounder (Post 5314813)
On my dash I have a blinking ATC light (automatic Traction Control).



I also have a ABS Blink Switch in the electrical bay (see picture). The blink switch has a green and orange led in it and it blinks a code. How it works is a mystery I hope someone can tell me. After random switch presses the ATC light on the dash will stay out for a while.



My questions:

1. In the production years 2006/2007 what brand ABS system did CC install?

2. Where is the control computer located?

3. Where is the module that controls the brakes located?

4. Where can I find a manual for my system?

5. Do you know the blink codes and sequences for the switch?

6. I know the differences between ABS and ATC so why do I get a ATC fail and not a ABS fail?



Did you ever receive any information about your questions?

My ATC light came on yesterday. I looked in my chassis manual and learned my 09 Affinity has a Wabco ABS system. I called them today and asked them for the blinking code translation form. They are sending it and I should have it tonight. I also asked about a dealer in my area that could service the system as most wonít know where to start. I found a local service center and will look at this Thursday.

gpounder 05-25-2021 09:25 PM

I spent quite a bit of time on this so here is what I know. I also used the WABCO service technician software to do some manual tests.

When the key is turned on the WABCO controller checks the ABS and ATC system by activating each relay in the brake system. It also checks each wheel speed sensor too. You can hear the relays if you open the door when you turn the key on. All my systems check okay but the ATC light still comes on the dash sometimes.

The WABCO tech support had me checking voltages and all was well. Also there were no error codes

I started to notice after a long drive and a very warmed up engine and charged battery the ATC light would not come on after starting the engine. In fact sometimes when I turn on the key but wait to start, the light comes on only after I start the engine.

So what I think is happening is the WABCO controller is being spiked by the starter. It may be a spike or low voltage, I do not know which.

I was just thinking about a work around. What if I supplement the power for the controller with the house batteries. Since I do not want to risk not having protective ABS braking if the house power is turned off I could wire it like this. All it would take is 2 diodes and a relay. When the key is on the relay provides power from the house battery through one diode to the controller. The other diode is put in series with the existing chassis battery source wire. The positive of each diode goes to the controller. Negatives go to each source. This way if one battery goes lower than the other, the other source would provide power. This would stabilize the power to the controller and just for good measure I would add a capacitor to absorb spikes.

I will report back if this works or not.

You asked where stuff is. Each wheel has a speed sensor. You will find two wires coming from it. There is a air valve interface that is connected to each brake along with solenoids that can make your brakes pulse. Just follow the air lines. The WABCO controller can be in the electrical bay under the driver or under the RV, lots of wires going to it.

2-Nickels 05-30-2021 05:48 PM

Quote:

Originally Posted by gpounder (Post 5765878)
I spent quite a bit of time on this so here is what I know. I also used the WABCO service technician software to do some manual tests.



When the key is turned on the WABCO controller checks the ABS and ATC system by activating each relay in the brake system. It also checks each wheel speed sensor too. You can hear the relays if you open the door when you turn the key on. All my systems check okay but the ATC light still comes on the dash sometimes.



The WABCO tech support had me checking voltages and all was well. Also there were no error codes



I started to notice after a long drive and a very warmed up engine and charged battery the ATC light would not come on after starting the engine. In fact sometimes when I turn on the key but wait to start, the light comes on only after I start the engine.



So what I think is happening is the WABCO controller is being spiked by the starter. It may be a spike or low voltage, I do not know which.



I was just thinking about a work around. What if I supplement the power for the controller with the house batteries. Since I do not want to risk not having protective ABS braking if the house power is turned off I could wire it like this. All it would take is 2 diodes and a relay. When the key is on the relay provides power from the house battery through one diode to the controller. The other diode is put in series with the existing chassis battery source wire. The positive of each diode goes to the controller. Negatives go to each source. This way if one battery goes lower than the other, the other source would provide power. This would stabilize the power to the controller and just for good measure I would add a capacitor to absorb spikes.



I will report back if this works or not.



You asked where stuff is. Each wheel has a speed sensor. You will find two wires coming from it. There is a air valve interface that is connected to each brake along with solenoids that can make your brakes pulse. Just follow the air lines. The WABCO controller can be in the electrical bay under the driver or under the RV, lots of wires going to it.



I had our coach into a Wabco service Center this week. They found crud between the sensor and ring on the passenger side tag. It has been cleaned up and recalibrated. We are planning a road trip in a couple of weeks in which it will have a better test.

They pulled all the codes codes and found the Wabco system had lost communication 75 times since it was read a number of years ago. The tech suggested that this does happen and chasing the issue could take days as the communication wiring goes to numerous devices.

Looking forward to the next trip to confirm all is well.

gpounder 05-30-2021 06:24 PM

Quote:

Originally Posted by 2-Nickels (Post 5771959)
I had our coach into a Wabco service Center this week. They found crud between the sensor and ring on the passenger side tag. It has been cleaned up and recalibrated. We are planning a road trip in a couple of weeks in which it will have a better test.

They pulled all the codes codes and found the Wabco system had lost communication 75 times since it was read a number of years ago. The tech suggested that this does happen and chasing the issue could take days as the communication wiring goes to numerous devices.

Looking forward to the next trip to confirm all is well.

That sound like a fix. Getting codes helps a lot.

I have installed my dual source diode idea. It worked great when applying power when the key was off. But when I hooked it up to power on with the key it failed again, never even got to start the engine.

Next step will be to add some capacitors to see if the initial power on spike is causing the failure.

gpounder 07-27-2021 05:15 PM

FIXED
 
After lengthy discussion with WABCO I learned exactly how the light circuit works. It has a dual function. The lamp driver is negative based. Grounds when lit but and optional mud snow switch will momentary ground the ground wire and cause the lamp to flash indicating the system is in mud/snow mode and stay flashing till the key is cycled.

When I got the RV the ATC lamp was out and I replaced all the lamps with LED's

The LED fooled the ECU thinking it was in mud/snow mode.

The fix was to use a indicancent bulb.

CountryFit 07-27-2021 05:36 PM

The moral of the story is - sometimes "good" is not necessarily good :D.

Twolanes 07-27-2021 07:53 PM

Quote:

Originally Posted by gpounder (Post 5849136)
After lengthy discussion with WABCO I learned exactly how the light circuit works. It has a dual function. The lamp driver is negative based. Grounds when lit but and optional mud snow switch will momentary ground the ground wire and cause the lamp to flash indicating the system is in mud/snow mode and stay flashing till the key is cycled.

When I got the RV the ATC lamp was out and I replaced all the lamps with LED's

The LED fooled the ECU thinking it was in mud/snow mode.

The fix was to use a indicancent bulb.

Thanks! Youíre experience has confirmed my suspicions. Right after I replaced the incandescent dash warning lamps with LEDís, my ATC began flashing intermittently. Iíll switch it back, but Iím going to look for a brighter incandescent bulb than was originally installed.
Thanks for posting!

dfuelman 07-27-2021 08:08 PM

In a former life, I was the caretaker of a fleet of Blue Bird blood mobiles for the local blood service. Went through a period with one of the buses where just about every 4 weeks, it would suddenly fail to start (would have to use the house batteries to jump it) and the ABS light would come on.

Take it to truck shop repeatedly for same repair, replace bad batteries and re-adjust ABS sensor's on the wheels. Happened about 6 months in a row. Every time, same story from the shop.

Happened to be speaking with the Bus converter out of Florida one day and mentioned to issue to him. He gave me a part number for an alternator and said if the dealer had one in stock, have it installed and it would fix the issue. Found out that there was a recall on the factory alternator's back when bus was new (didn't know anything about recall???) Shop install new Alternator and no more issues.

Alternator was over charging the batteries and cooking them and the high voltage spikes were causing the WABCO computer to turn on the ABS Light on the dash. Never had another issue with that unit until a driver flipped it over later that year and destroyed it.


All times are GMT -6. The time now is 12:53 PM.

Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2021, vBulletin Solutions, Inc.