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View Full Version : 2006 T1N stuck in park; help diagnosing


outwestbound
12-11-2018, 03:41 PM
Hi. Have a T1N 2006 3500 (auto trans, 77,000 miles); Winnebago Itaska Navion 23J motorhome.

I was stuck in park this am. Read forum, then used pencil in the selector lever hole for manual operation, which freed up the shifter on my automatic transmission.

I'm trying to understand what's wrong and whether I've damaged the vehicle. I drove the rear passenger side onto 6" "RV" blocks and left it on the blocks for 6 weeks. When the transmission locked up, I thought I'd damaged the transmission.

While up on blocks, I replaced the reverse lights with LED. I'm not sure what is happening.

Here's what's odd. The manual says the brake must be depressed to start the vehicle. But, it starts fine without touching the brakes. So I figured this this "brake light switch" is broken: https://europarts-sd.com/switch-brakelight6pin2002-2006.asp

If the switch is broken, wouldn't the brake lights not work? My brake lights work fine, either with the ignition key on or running. The brake lights don't (to my knowledge) come on unless I depress the pedal. I looked at the switch and the white plastic actuator pin (or whatever it's called) seems to come out and in alright (with some tension).

I understand that, if the brake light switch is broken, the vehicle doesn't get the signal that the brakes are depressed, so the transmission lever remains locked in park. Right? But my brakes work fine, yet my transmission lever remains locked in park, unless I use the "pencil" manual selector lever method.

I don't know if I've damaged my transmission putting it on the blocks on one side in the rear or what?

Any thoughts?


John

Midwestdrifter
12-11-2018, 04:21 PM
No need to panic, you probably just caused a minor issue.

Messing with the brake lights can in theory disrupt the brake switch signal, which is shared with the tail lights. Try unplugging your new LED lights to see if that caused the issue. If the ABS module does not see the brake switch signal, the shifter will not release the electronic shift lock. Your brake switch is probably fine. You don't need to depress the brake to start the engine.

I am about 75% sure the LED lights are causing the issue. You may need to switch back to the old ones, or just wire a resistor across the lines to fix the issue.

My vans shifter assembly has a bad connection on the circuit board inside. So the shift lock will fail most of the time within about 3 seconds of pressing the brake pedal. I have been meaning to fix it, but it does me zero harm. I just keep a pen near the shifter assembly!

outwestbound
12-11-2018, 04:49 PM
No need to panic, you probably just caused a minor issue.

Messing with the brake lights can in theory disrupt the brake switch signal, which is shared with the tail lights. Try unplugging your new LED lights to see if that caused the issue. If the ABS module does not see the brake switch signal, the shifter will not release the electronic shift lock. Your brake switch is probably fine. You don't need to depress the brake to start the engine.

I am about 75% sure the LED lights are causing the issue. You may need to switch back to the old ones, or just wire a resistor across the lines to fix the issue.

My vans shifter assembly has a bad connection on the circuit board inside. So the shift lock will fail most of the time within about 3 seconds of pressing the brake pedal. I have been meaning to fix it, but it does me zero harm. I just keep a pen near the shifter assembly!

Hey MWD - your racking up a lot of free lunches ha ha

I hate to loose the LED reverse lights I need to see at night out of the rear camera, but I'll try this and see. I ordered a new brake switch just to have it, whether I need it now or not. If it's the LED lights, I'll throw the new switch into the parts compartment.

Midwestdrifter
12-11-2018, 05:00 PM
Sorry, I misread your post. the LED reverse lights themselves won't cause this issue. However, shorting out the brake light bulbs or wires can cause a no shift error. As a test you can try disconnecting the entire light housings if possible. This may set a warning light on the dash. Then connect one or the other and swap to see if the issue returns.

A good scanner can read the ABS module. You can see if the ABS module is "seeing" the brake switch being opened/closed. There are two switches (in the brake switch assembly) in parallel for safety. One goes open when the other closes and vice versa.

autostaretx
12-11-2018, 05:17 PM
The brake light switch has actually *two* switches inside its package .... one controls the tail lights, the other informs the ECU that you're stepping on the brakes.

So it's perfectly possible for only one of those two functions to be operating properly (or improperly).

In a T1N Sprinter, a commonly needed "fix" was to reset the brake switch ... you crawl down in the pedal area and push (with your hand) the brake pedal ... and look for the plastic stalk (from the switch) that follows it down.
With the pedal still depressed, use the other hand to *pull* the stalk "gently but firmly" out to the limit of its travel.
Then release the stalk, and gently allow the brake pedal to rise back up to the "normal" position.

See if that helps.
------------

The "stuck in Park" is merely due to a solenoid that the ECU (and TCM) has not deemed "OK to release".
Among the votes on that matter are: brake pressed? (if the tell-the-ECU half is being iffy, that can cause it); engine running? (can be fooled by shorted/mis-wired tail lights) and some other items.

--dick

outwestbound
12-11-2018, 06:19 PM
Still stuck. Frustrated. Changed the LED reverse lights with stock bulbs, no help. Tried with no bulbs, no help. I checked all fuses. Found a 7.5 blown for running lights, but replacing that didn't help. Maybe blew that taking out the front headlight to look at the espar, but I reattached that this morning. I found a procedure to "reset" the brake switch by pulling the white plastic plunger out, but no help.

I worked on a switch that tells the vehicle when the emergence brake is set. I'd pulled a lead off by putting things down there and the slide would not work is what happened. All I did was put the leads back on and tape it. I don't know if it's mercedez or Winnebago. It's at the base of the parking brake lever and has two simple contracts, because something I had on the floor pulled one of the contacts loose and the slide wouldn't work. (Winnebago only allows slide to operate when brake is set). I'm thinking somehow this is the issue. I pulled the two leads off this morning fiddling with possible solutions and connected them with a paper clip, which illuminates the brake light on the dash. I need to reattach these leads on the switch posts and see if this helps.

Midwestdrifter
12-11-2018, 06:40 PM
Do you have access to a scanner, such as the autel MD802? You can use that to see if one or both of the brake switch contacts is closing.

The shifter is a true module, so it can be scanned with a good scanner. This may report a wiring or canbus fault. These do not usually set a check engine light.

To my knowledge, the Ebrake switch does not have any impact on the park lock.


Regardless, the park lock is not a mission critical item. It may be annoying to bypass every time though!


Given that you were working on the tail lights, I would focus on a wiring fault there. Double check the brake light fuses, and the housings for pinched wires. Reseat the brake light bulbs, etc.

outwestbound
12-11-2018, 07:02 PM
Sorry, I misread your post. the LED reverse lights themselves won't cause this issue. However, shorting out the brake light bulbs or wires can cause a no shift error. As a test you can try disconnecting the entire light housings if possible. This may set a warning light on the dash. Then connect one or the other and swap to see if the issue returns.

A good scanner can read the ABS module. You can see if the ABS module is "seeing" the brake switch being opened/closed. There are two switches (in the brake switch assembly) in parallel for safety. One goes open when the other closes and vice versa.

I'll see if my MB icard II reader can see he ABS.

Because I was looking at the espar, I had a headlight assembly hanging down, and it got rained on several times (but the car was off). It works fine.

The rear taillight assemblies also hung down, probably in the rain also, for a while. I'm not sure. I just cleaned one up that had corroded contacts. They work fine using the brake pedal and reverse.

I found a 7.5 amp "daytime running" lamp fuse blown and replaced it. It doesn't blow again.

I'll keep working at it. Shifter still locked up.

Cheyenne
12-11-2018, 07:03 PM
Winnebago only allows slide to operate when brake is set.


If Winnebago have done something weird like this then have they possibly wired something else in so you cannot drive off if the slide is not fully retracted?

Try extending and retracting the slide, it just may help!

Keith.

outwestbound
12-11-2018, 08:06 PM
If Winnebago have done something weird like this then have they possibly wired something else in so you cannot drive off if the slide is not fully retracted?

Try extending and retracting the slide, it just may help!

Keith.


Between the overly anal German engineers and the liability avoidance of an American family motorhome product manufacturer, this thing is a freak show in terms of electronic crapola ha ha ha I bought the first year model Winnebago did on a Sprinter chassis. I'm sure they changed some stuff, but it's still a cool little vehicle.

outwestbound
12-11-2018, 09:19 PM
The brake light switch has actually *two* switches inside its package .... one controls the tail lights, the other informs the ECU that you're stepping on the brakes.

So it's perfectly possible for only one of those two functions to be operating properly (or improperly).

In a T1N Sprinter, a commonly needed "fix" was to reset the brake switch ... you crawl down in the pedal area and push (with your hand) the brake pedal ... and look for the plastic stalk (from the switch) that follows it down.
With the pedal still depressed, use the other hand to *pull* the stalk "gently but firmly" out to the limit of its travel.
Then release the stalk, and gently allow the brake pedal to rise back up to the "normal" position.

See if that helps.
------------

The "stuck in Park" is merely due to a solenoid that the ECU (and TCM) has not deemed "OK to release".
Among the votes on that matter are: brake pressed? (if the tell-the-ECU half is being iffy, that can cause it); engine running? (can be fooled by shorted/mis-wired tail lights) and some other items.

--dick


Thanks Dick.

I did try the reset you described, but no help. I have some new info. My reader showed code P1817-002 "reversing light has short circuit to positive or discontinuity". I changed out the reverse lights with LEDs, but left the assemblies exposed to weather. I cleaned up the contacts, cleared the code, but shill shifter is stuck.

Also, code reader said on actual values:
1) reverse lamp off. I put it in reverse, then is said "on"
2) stop lamp switch, not operated. pushed down on brake, still says "not operated"
3) status of locking solenoid, not operated. same result as 2 above.

The p1817-002 code cleared and did not return. I took apart the tail light assemblies and clean them some, then re-seated the bulbs, as MidWestDrifter recommended. The code doesn't come back after clearing it.

But, shifter still locked up. I wonder if rain on the tail light assemblies shorted, coded and in that process, ruined the side of the brake light switch that communicates with the ECM?? All exterior lights work fine now, so given 1-3 above, I wonder if replacing the brake switch will fix this?? One is on the way from europarts sd, so we'll see.

I don't know what else to do.

Midwestdrifter
12-11-2018, 09:23 PM
Its possible the switch died. With no change in the stop lamp indication that could be the case.

outwestbound
12-11-2018, 09:38 PM
Its possible the switch died. With no change in the stop lamp indication that could be the case.

This is what I'm thinking (hoping even) at this point. I don't believe in coincidence, so the switch dying at this time I can't buy. But if I caused that code shorting the tail lights, my hope is that careless act of stupidity on my part also killed the switch. I paid about $25 for the switch, and if that fixes it, that will be a cheap learning opportunity.

Midwestdrifter
12-11-2018, 09:45 PM
Regardless of whether not this switch fixes the problem it is a good part to having your spares box.

outwestbound
12-11-2018, 09:49 PM
Regardless of whether not this switch fixes the problem it is a good part to having your spares box.

Indeed. I have spares for all Winnebago and Sprinter fuses and relays - wow - stupid long list! I'm going to have to cut down on my tools & supplies. Carrying too much weight for stuff I might need. In this rig, I'm not going to be off the beaten path too far, so I'm going to cut back on weight. From your debrief notes from Australia, looks like you were a little fat.

I'm down to a final, big decision on habitation area heating. I'll post on the build thread.

autostaretx
12-11-2018, 11:52 PM
Thanks Dick.

I did try the reset you described, but no help. I have some new info. My reader showed code P1817-002 "reversing light has short circuit to positive or discontinuity". I changed out the reverse lights with LEDs, but left the assemblies exposed to weather. I cleaned up the contacts, cleared the code, but shill shifter is stuck.

Following the time-honored (and frequently successful) approach of "undo whatever you did last",
try REMOVING the LEDs. You can leave the sockets empty.

See if that has an effect.

--dick

Midwestdrifter
12-11-2018, 11:57 PM
Ah, now I remember. If you back feed 12V into the reverse light circuit, it will power up half the vans modules. Maybe this is confusing your ECM/Shifter? Its worth a try.

outwestbound
12-12-2018, 12:02 AM
Ah, now I remember. If you back feed 12V into the reverse light circuit, it will power up half the vans modules. Maybe this is confusing your ECM/Shifter? Its worth a try.

Your over my head with this one ha ha.

Midwestdrifter
12-12-2018, 12:04 AM
Your over my head with this one ha ha.

If you take 12V power and connect it to the reverse lights, the whole dash will light up, the ATC will turn on. Which is really surprising if you haven't put the key in!

outwestbound
12-12-2018, 12:12 AM
If you take 12V power and connect it to the reverse lights, the whole dash will light up, the ATC will turn on. Which is really surprising if you haven't put the key in!

Do you think I've got some power backfeeding? I'm just not sure if you think I should push some 12v back from the tail lights to try to fix this issue I'm having.

Midwestdrifter
12-12-2018, 12:17 AM
I am not suggesting you do it, I am simply saying that some really weird stuff can happen when the taillights are involved!

Patrick of M
12-12-2018, 12:18 AM
Do you think I've got some power backfeeding? I'm just not sure if you think I should push some 12v back from the tail lights to try to fix this issue I'm having.
I donít think he is suggesting that you create a back feed on purpose, just that a miss wiring can back feed by accident, and this will confuse the system

outwestbound
12-12-2018, 12:29 AM
I donít think he is suggesting that you create a back feed on purpose, just that a miss wiring can back feed by accident, and this will confuse the system

I see. I appreciate your perspective. It's weird. Yes, mine is Christmas treed together between the MB chassis and Winnebago rear end. Man, it's weird for sure. Sometimes, it's hard to figure out which manufacturer did what.

I'm gonna post some thoughts on your build thread.

nestorio
04-20-2019, 07:41 AM
:bow: My abs lights come on I can't set cruise and shifter gets stuck on park. I have to stop the van restart and shifter works but abs light continue to come on Help:idunno::bow:

nestorio
04-20-2019, 08:37 AM
:bow: My abs lights come on I can't set cruise and shifter gets stuck on park. I have to stop the van restart and shifter works but abs light continue to come on Help:idunno::bow:

outwestbound
04-20-2019, 01:13 PM
:bow: My abs lights come on I can't set cruise and shifter gets stuck on park. I have to stop the van restart and shifter works but abs light continue to come on Help:idunno::bow:


Do you have a scanner? If not, maybe stop in a retail place like AutoZone and see if they can scan your ECM for error codes.

My issue was that I shorted out my brake light switch, which is directly behind and activated by the brake pedal. I replaced the switch and the issue was resolved. My problem was caused by my carelessness in allowing rain to get into the rear tail lights while I was working on them.

I hope someone can chime in on your issue. I'm not sure. Good luck .

autostaretx
04-20-2019, 07:04 PM
Among MANY other reasons, the ABS light will come on if a wheel speed sensor isn't working.

You really want to either start a new thread, or search through the dozens/hundreds of ABS ON! threads.

--dick