No Brake Lights

Topic: No Brake Lights (Read 1496 times) previous topic - next topic

No Brake Lights

June 08, 2012, 10:43:44 pm

This being my last day in Nac and being late on Friday afternoon, that means that Murphy's law is lurking around just waiting to strike! That's right...this afternonn when Greg at Xtreme whas driving Forrest into the bay for final touches, I noticed that the brake lights were not working. Greg said "if it can be fixed by applying paint to it, we can do the brake light job"...very funny.

I went to MOT for some help and Mike Rodgers dropped what he was doing to try to help. He spent some time finding out the components that could have gone bad and gave me the part numbers as it was late and every one of the techs were working on coaches already. I purchased a brake switch and a 15 amp breaker which Mike specifically found out from the electrical drawings location.

Wnr back to Xtreme and started taking voltage readings, and as I was messing around, discovered that the breaker was fine, but the brake switch might be suspect. With Greg applying the brakes I had intermittent voltage readings. It turned out that by probing around I must have cleaned out some corrosion and the brake lights worked just fine.

Dodged another one! Still scheduled to head north tomorrow.

Peter

Re: No Brake Lights

Reply #1 – June 08, 2012, 11:28:36 pm

Quote from: Peter & Beth – June 08, 2012, 10:43:44 pm

... It turned out that by probing around I must have cleaned out some corrosion and the brake lights worked just fine. ...

"Probing around" is similar to "percussive maintenance." Some stuff just needs to be exercised or tapped. I noticed my cruise control quit working properly shortly after I had put hard pressure on the service brake pedal a few times. After a couple of lighter taps of the brakes, the cruise control started working again. I expect the brake lights may have been stuck in the "on" mode. Some alternative "range of motion" movements may have helped. It's kind of like "probing around." (That's my story ... believe or don't.

Your experiences may vary.)

Best wishes for safe and enjoyable travels home!

Re: No Brake Lights

Reply #2 – June 09, 2012, 09:38:23 am

Peter,

Where did you find the brake light switch?

Re: No Brake Lights

Reply #3 – June 09, 2012, 08:04:32 pm

Update:

John, my brake light switches (2) are in the first compartment street side (where most have the genset fans).

Today I found the hard way that the brake lights are not working. Had Forrest on cruise...happily showing off his new pampered look...and when I applied the brakes, the cruise kept right on cruising...

Got to Yuma, TN w/o brake lights, but mostly if not all Interstate. Too tired to fiddle with stuff now, but in the morning I'll try again.

Peter

Re: No Brake Lights

Reply #4 – June 09, 2012, 08:46:06 pm

Peter,
I've had difficulty with these brake switches and their King Throttle Control functions several times in the past.
Each time I removed the wires from the switches, cleaned the terminals, lubed with dielectric grease and relanded them, and the problems cleared for a long time afterward. Not sure why I have had these problems repeat (two or three times in 14 years), but that's all it took to clear them.
I will say that when coach start battery circuits have voltage strength problems (through poor supply connections, poor grounds, excessive dash solenoid voltage drop, or battery age issues) the probability of the switches and King Throttle Control issues seems to increase.
I recall you recently changing your start batteries. Start battery circuit issues may also manifest as dash voltage readout erratic behavior, reading lower than normal for no apparent reason, engine temperature acting strangely, going high for no good reason, etc.
Good luck and let us know what you find.
Neal

Re: No Brake Lights

Reply #5 – June 09, 2012, 09:09:51 pm

Neal,
Thanks for the heads-up...in fact the temp readout and the voltage readout are off a bit...190 degrees and 13 VDC at the dash gauge but 13.8 VDC on the Javelina readout.

I'll clean up the brake switch terminals tomorrow 1st thing and check it out. The batteries seem to be fine, but who knows?

Peter

Re: No Brake Lights

Reply #6 – June 09, 2012, 10:17:48 pm

Thanks Peter.

Re: No Brake Lights

Reply #7 – June 10, 2012, 07:20:13 pm

Well...Today I cleaned the terminals a bit on the brake light switch (I think). I cleaned the one closest to the door. There are two of these switches, and I couldn't get the terminals in the second switch real well. On the drive home the brake lights worked intermittently as evidenced by the cruise not disengaging with the application of the brakes...Yeah, you don't want to try this when you really need to slow down...

Now that I'm home, I'll have more time to troubleshoot. MOT sold me a 15 amp auto reset breaker that does not fit in the main panel in front of the driver...wrong spec.

Peter

Re: No Brake Lights

Reply #8 – July 05, 2012, 09:49:44 am

I ordered another brake light switch so I could replace both at the same time. I've also ordered a 15 amp Type 1 auto reset fuse (thanks Barry L. for the web site) to replace the brake circuit fuse which may be faulty. My question is in connection with the removal of the brake light switches.

Are these switches crewed into an air fitting so all I need to do is unscrew the switch? Or, are these switches bolted in place so I would need to use a couple or wrenches to remove these?

Thanks for your help. I'm in Florida today w/o coach but will return by Tuesday and need to get to this job soonest

Peter

Re: No Brake Lights

Reply #9 – July 05, 2012, 01:19:13 pm

Peter, if your connections are the flat bayonet type try closing up the female half a little bit for a tighter fit. A pliers works well if used judiciously.
I had repeated problems with our brake switch connections on our '89. Tried cleaning them off, dielectric grease, even coated them with liquid tape to prevent them corroding or rattling loose. Nothing worked until I did the "crimp" thing.

Re: No Brake Lights

Reply #10 – July 05, 2012, 03:02:01 pm

They should just screw out and then you can screw in the new switch, the thread is a pipe thread can't remember if 1/8 or 1/4

Re: No Brake Lights

Reply #11 – July 05, 2012, 03:29:33 pm

Quote from: red tractor – July 05, 2012, 03:02:01 pm

They should just screw out and then you can screw in the new switch, the thread is a pipe thread can't remember if 1/8 or 1/4

Thanks...It looks like that, but never having done this job before, I get the newby jitters... $:-\$

Quote from: nitehawk – July 05, 2012, 01:19:13 pm

Peter, if your connections are the flat bayonet type try closing up the female half a little bit for a tighter fit. A pliers works well if used judiciously.
I had repeated problems with our brake switch connections on our '89. Tried cleaning them off, dielectric grease, even coated them with liquid tape to prevent them corroding or rattling loose. Nothing worked until I did the "crimp" thing.

Yup...All these connections are gone...just about. And, that's with cleaning and lubricating.

Thanks to all,

Peter

Re: No Brake Lights

Reply #12 – July 14, 2012, 04:43:25 pm

Today I finally got around to replacing the brake light switches. The toughest part of the job was performed by Beth. She went to Lowe's to get a 7/8" wrench which I did not have. Harbor freight did not have just the wrench. They had plenty of large sets, which I don't need.

I cleaned all the connectors and used liberal amounts of dielectric grease to try to keep the corrosion down as much as possible. This area (1st compartment driver's side) is definitely an annual inspection/lube area of the coach.

BTW, I did not replace the type 1 auto reset fuse (15 amp, wire T3 Location #32) located in the fuse panel in front of the passenger seat.

Forrest is now happy that he can tell folks behind him that he needs to slow down or worse yet...stop...

Peter

Re: No Brake Lights

Reply #13 – July 14, 2012, 05:24:50 pm

That's good news and good work regarding your replacement of the brake light switches.

Here is an observation related to "no brake lights." On our 1997 U295, slowing by using the retarder joystick does not cause the brake lights to illuminate. I was curious, so Marilyn followed me and watched for brake lights as I applied the retarder and did not apply the brakes. She reported that the brake lights did on illuminate. The brake lights work fine with application of the service brake.

Also, application of the retarder without using the service brakes will not disengage the cruise control. On a long downhill grade, I set the cruise control and the retarder (via joystick) to see what would happen. When cruise control released the accelerator all the way, the retarder engaged; the coach slowed a bit; the cruise control pressed the accelerator; the retarder disengaged; the cruise control released the accelerator; the retarder engaged; ...

The joystick was not original equipment on our coach. MOT installed the joystick kit from Allison. Does engagement of the retarder illuminate brake lights on other coaches?

Re: No Brake Lights

Reply #14 – July 14, 2012, 05:46:41 pm

(edited for clarity)

My drawing No. 2198 shows wire #33 from the brake light switch to the King Cruise, then application of the treddle valve (foot brake) will disengage the cruise control through this circuit. Drawing No. A-5725 shows the #33 wire to the King Cruise module. There is no drawing (I'm missing some) that shows the Allison Retarder/Joy stick connected to the brake circuits.

The U270 wiring indicates that your experience (J. D.'s) is mine as well...joystick does not override the King Cruise and is not wired to engage any of the brake circuits.

Hope this helps. Although I remember reading (old Yahoo forum) that in some coaches the retarder joystick can disengage the cruise as well as operate the brake lights (by default). These units may use some other throttle system other than the King Cruise.

Peter

Re: No Brake Lights

Reply #15 – July 14, 2012, 07:54:46 pm

I am changing brake/tail lights from incandescent to LED as we have a need to get into where the lights are mounted (what genius thought up *that* system but left the isolator board out in the open?). These LEDs are now available over-the-counter at O'Relly Auto Parts stores. They're not cheap but what they do is reduce the loads on aging wiring.

As an example: I have a 1972 Carver Santa Cruz sport-fishing boat (25'). It's a lovely little boat and ideal for Puget Sound but the salt air has not been kind to the wiring. With incandescent bulbs I could turn one ONE (and only one) light. If I turned on another light - any light - then no light would turn on. Rather than go through the wiring I just moved all lights to LEDs and the current draw was so low that now I can turn all the lights on with no problems. This is with zero changes to the wiring and the connections.

As our coaches age and the wiring inevitably corrodes the change to LEDs will mean that more of your lights will be on and bright. Plus the LEDs last much longer. With the stock at O'Reilly you can just take the old bulbs in and find a replacement.

I have no connection with O'Reilly, btw. I was just happy to see that they stock at least some LEDs.

Craig

Re: No Brake Lights

Reply #16 – July 14, 2012, 08:16:31 pm

Quote from: J. D. Stevens – July 14, 2012, 05:24:50 pm

Also, application of the retarder without using the service brakes will not disengage the cruise control.

Must be installation-dependent. On our '03, retarder activity disables cruise and you have to push the joystick all the way back forward and hit "resume" to re-enable cruise.

-M

Re: No Brake Lights

Reply #17 – July 14, 2012, 09:29:31 pm

I just returned from a 4 week, 3K mile trip and the retarder when used alone without brakes was not turning off the cruise control. Prior to this trip the retarder would disengage the cruise control when the joy stick was used. I suspect that the wiring connections need to be checked, cleaned, and tightened. A few times, I was driving on some up and down hills and just left the joy stick in about the 3rd position so that the retarder would engage going down the hills, the cruise control did not disconnect and would apply the throttle going up the next hill. I liked that, but I know that is not the way it is supposed to work. Near the end of the trip, once or twice I noticed the retarder light come on when I got off the throttle with cruise control off and joy stick in the off position. Although the retarder light was on, no retarding seemed to be occurring. Retarding with the service brakes was normal and turning off the retard switch turned off the retarder as it should.

Re: No Brake Lights

Reply #18 – July 14, 2012, 09:48:21 pm

Jerry,
Do you still have the King Cruise throttle control? I have some drawings missing so I cannot determine the wiring to the King Cruise and the Allison. The drawings I have (U270 for 95, 96 & 97) do not show any circuits from the brake light to the Allison Retarder or Joy stick.
Peter

Re: No Brake Lights

Reply #19 – July 14, 2012, 10:14:36 pm

Peter,

Yes, I still have the King Cruise throttle control. I don't remember ever seeing any wiring diagrams for the cruise control, so I don't think I have any.

Re: No Brake Lights

Reply #20 – July 14, 2012, 10:33:13 pm

I'll have to take a test drive with the new brake switches and determine if the joystick retarder disengages the cruise. This also means that the brake lights would also be engaged by the use of the joystick. There was much corrosion going on at the circuit where the brake light switches are located. If there is a circuit for the joystick/Allison, it may have been disabled by all the corrosion. I'll report back in the future.

Peter

Re: No Brake Lights

Reply #21 – July 15, 2012, 02:03:48 am

King Control (cruise control and throttle control) circuit board has a connection to the rear brake light circuit for two purposes.
1) If cruise control is active and the brake light come on, cruise control turns off, only to come back on with a new set or resume.
2) If the throttle control circuit does not see a ground connection through
a brake lite bulb, the coach will only accelerate to about 10 mph no matter how hard the throttle pedal is pressed. Burned out brake light bulbs will cause this situation. And a missing wire connection to brake lights will also cause this problem. King wants to know it can sense brake lights, so it can turn cruise off when brake lights will come on. If King does not see ground, it assumes brake light wire is missing.

When the transmission retarder joy stick is added, a relay is added just to turn on Foretravel brake lights. Allison does not require this relay to activate the retarder from the joy stick.

When the retarder is activated by using the brake pedal, brake lights turn on from air pressure switches.

If someone adds a joy stick and does not add the relay, joy stick retard will not turn on brake lights. And if driving on a highway with cruise control on and joy stick in a retard position, and the coach goes down a dip, the accelerator goes to zero position, retard comes on, and when the coach reaches the bottom of the dip, the coach will again accelerate and retard will go off.

If the relay is in place because the joy stick was originally part of the coach or the relay added, joy stick retard action will turn on brake lights and immediately turn off cruise, which stays off and must be reactivated manually.

One can have a dash switch on the new relay control wire to choose between having brake lights come on with joy stick retard, or not come on.

Re: No Brake Lights

Reply #22 – July 15, 2012, 09:04:44 am

Barry,

Thank you for the information regarding the interaction of brake lights, throttle, and King control.

Your description coincides with my experience and the behavior of our system with the joystick that was added to control the retarder. I don't have a preference regarding the behavior, but I like to understand what is going to happen and what I should expect.

The information about the requirement for sensing a good brake light circuit is new information for me. It is valuable information to the person whose chose won't accelerate about 10 mph. It does not apply to our coach with respect to basic throttle operation. My understanding is that we still use the King control as a cruise control. The throttle is an air operated system that was installed by the previous owner after some unsatisfactory experiences with the King control.

Re: No Brake Lights

Reply #23 – July 15, 2012, 09:07:27 am

Barry,
Which drawing depicts this circuitry? Where is the relay placed physically, and do you know which wire number?

Thanks, Peter

Re: No Brake Lights

Reply #24 – July 15, 2012, 09:26:33 am

I have that drawing at home, but right now am at the factory, just got here last night. When I get back home if it is still needed, I will put the drawing on here. It is the installation of a bosch type relay

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