Foretravel Owners' Forum For owners and Fans of Foretravel Motorcoaches September 11, 2025 ...

ABS dash light affect the retarder?

June 11, 2014, 10:01:57 am

I have a ABS dash light and was told by MOT that was alright to continue driving until I get it repaired. What I was wanting to know if the retarder is affected by the ABS system?

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Re: ABS dash light affect the retarder?

Reply #1 – June 11, 2014, 10:03:01 am

I forgot to give the FT info 1998 U270.

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Re: ABS dash light affect the retarder?

Reply #2 – June 11, 2014, 10:36:16 am

John,

Everything works fine, just no ABS function.  Repair when you have time, no rush.

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Re: ABS dash light affect the retarder?

Reply #3 – June 11, 2014, 12:48:27 pm

May or may not be fixable as the midland/Grau unit we have is obsolete.

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Re: ABS dash light affect the retarder?

Reply #4 – June 11, 2014, 07:15:41 pm

Retarder is disabled when ABS is not working.  You can meter the wheel sensors to locate a bad sensor. Schematic is on the inside of the ABS control box cover.  Sensors available on Ebay.

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Re: ABS dash light affect the retarder?

Reply #5 – June 11, 2014, 07:24:39 pm

Tom,

My 1995 U320 ABS light has been ON for years by my choice to not fix the ABS system.  My retarder has never failed to operate every time I have ask it to.  My retarder switch is ON all the time and engages each and every time I move the joy stick or step on the brakes.

If ABS failure disarms your retarder, you may very well have problem that needs looking into.

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Re: ABS dash light affect the retarder?

Reply #6 – June 11, 2014, 07:38:10 pm

Hi Tom,
  When I had FOT do some rear brake work they moved the ABS sensor. The ABS light came on. The retarder was still functioning as usual. FOT used a long pry bar to "adjust" the sensor later the same day. All was well.
Raymond

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Re: ABS dash light affect the retarder?

Reply #7 – June 11, 2014, 07:46:04 pm

My ABS light has been on for a time.  Another good use for VMSpc: It tells me specifically that the rear driver's side sensor has low current (IIRC).  Not a worrysome event.  I just haven't gotten to it.  I should have checked when I  got my new tires 2 weeks ago...but forgot.  Retarder and brakes work just fine.

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Re: ABS dash light affect the retarder?

Reply #8 – June 12, 2014, 09:20:34 am

I've had some intermittent problems with an ABS light.  This seems to be linked to pulling a toad, suspect either excess current draw in braking circuit or feedback of some sort.  Do have diodes installed between coach and tow.  Be nice to get this sorted. 

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Re: ABS dash light affect the retarder?

Reply #9 – June 12, 2014, 09:54:18 am

Where would I look for the ABS control in 1998 U 270?

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Re: ABS dash light affect the retarder?

Reply #10 – June 12, 2014, 10:15:09 am

On my coach it is on the roof of the first storage bay

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Re: ABS dash light affect the retarder?

Reply #11 – June 14, 2014, 06:21:49 pm

The answer to the original question is yes and no.  On my 95 U280se the retarder is controlled by a relay in the ABS controller.  Others must be different.  You would have to check the schematics on your coach to verify how it is wired.  On my coach you can pull the relay and install a jumper wire to keep the retarder active in case of ABS failure.

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Re: ABS dash light affect the retarder?

Reply #12 – June 15, 2014, 11:33:47 pm

In our 99 U270, the ABS controller is on the ceiling in the (center) storage bay.

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