Community Forums

Just For Fun · 09-06-2021, 10:02 AM

Here's an odd ball one for you:
I have a 2006 Sig with an ISX600 Allison 4,000 trans

First: Driving last night, the transmission stuck in 4th gear. It would NOT automatically or manually shift up or down from 4th gear to any other gear. Fortunately the engine is strong enough to move us up and down hills, towing a full size pickup. Not the best situation/strain on this engine. But... We were unable to pull off the road since we were on winding mountain roads, at night and will no lights from highway type lighting. Think dark-twisting-mountain roads!!!!

Secondly: As we're driving, the headlights started going dim. Finally the dashboard lights went out as well as the headlights. The engine was still running well (but in 4th gear) but a red dashboard light came on "CHECK TRANS." Again, we were unable to pull off the road due to being on winding mountain roads with ever diming head lights. But I kept a vigil on the "Trans Temperature Gage" that showed relatively cool. ALL GUAGES WERE SHOWING NOTHING ABNORMAL IN TEMPERATURES! No increase in running temperature. I attempted to get a number of the actual Trans Temperature, but again, running with minimal road lights in the mountains on twisting roads is a bit tricky in itself.

Once we got to a safe place to pull over, I was really concerned about shutting down the engine with a fear of it not restarting - still being stuck in 4th gear rather than Nutral. But, due to the "smarts" wiring in this otherwise excellent coach, the front door would NOT unlock while the engine is running!!!!! So, I shut it down. This morning I turned on the engine; it started up in Nutral and started find, no resistance and moved into 1st gear when requested.

One other item: As we were driving and had NO headlights, I noticed that the "VOLT" meter on the dash was registering Zero (using a flashlight)!!! When I depressed the "Battery Boost" switch, the dash and headlights came on strong for about 30 seconds. But when I released the Battery Boost switch, within 30 seconds the lights turned off and the VOLT guage went to Zero. It also registers "12" this morning when I started the engine - but I also have the generator running. Not sure if that makes a difference. I also check the batteries last night and they registered about 12.9. Generator running now to bust them back up.

I checked the "engine" oil this morning; full. I can't find where the Trans oil dip-stick is. Anyone know?

Anyone had a problem like this? All educated ideas/suggestions wanted?

Thanks.

wolfe10 · 09-06-2021, 10:08 AM

Sounds like an electrical problem between the chassis battery bank and the "ignition hot" items. A good place to check is the IGNITION SOLENOID. One large lug has chassis battery voltage all the time. The other large lug has that same voltage when the ignition is on.

So, start by checking for good clean, tight connections at the chassis battery, including ground connection.

With your symptoms, I would NOT start by thinking the transmission has an issue. It is electronic, and if it looses 12 VDC, it goes into safe mode.

But, easy to check for transmission electronic issues from the driver's seat. With ignition on, engine off:

Push up and down arrows at the same time on the Allison shift pad.

Push them again.

That will bring up d-1 (diagnostic code 1). Record it. Push the mode button to bring up d-2. Continue until you get d-"something" and - - meaning there are no more diagnostic codes.

Turn off the ignition and look up the codes in your Allison book or online.

shootist · 09-06-2021, 10:13 AM

I agree it is electrical. Frame grounds at the dash, inverter, starter, chassis batteries ,engine and coach batteries. Everytime I thought I cleaned them all I would come across another. It will do it again if not found. Like the old 60s fords just quitting while driving down the road when the battery corroded up on the terminals. Clean the positive connections as well. It's most common during weather changes, hot to cold. Dry to damp etc.

Just For Fun · 09-06-2021, 10:18 AM

Quote:

Originally Posted by wolfe10

Sounds like an electrical problem between the chassis battery bank and the "ignition hot" items. A good place to check is the IGNITION SOLENOID. One large lug has chassis battery voltage all the time. The other large lug has that same voltage when the ignition is on.

So, start by checking for good clean, tight connections at the chassis battery, including ground connection.

With your symptoms, I would NOT start by thinking the transmission has an issue. It is electronic, and if it looses 12 VDC, it goes into safe mode.

But, easy to check for transmission electronic issues from the driver's seat. With ignition on, engine off:

Push up and down arrows at the same time on the Allison shift pad.

Push them again.

That will bring up d-1 (diagnostic code 1). Record it. Push the mode button to bring up d-2. Continue until you get d-"something" and - - meaning there are no more diagnostic codes.

Turn off the ignition and look up the codes in your Allison book or online.

I like this!!! THANKS!!!

8.3Oilbuner · 09-06-2021, 10:19 AM

Good morning Just For Fun; Have to agree with Wolfe10, I also think you have an electrical problem. When voltages drop the ECM for the transmission does not like this and does strange things. Also the fact that your headlights went dim is another clue. As to a dipstick for the transmission, not sure if you have one. Check in the engine compartment for a transmission fill cap. It might have a dipstick built into the cap. You might just have to check the level on your shift pad on the console because your model may not have a dipstick and just a fill port. I think your fist step is to find out why the voltage drop and go from there. With the generator running you should be getting at least 13.5V at the batteries. Hope some of this helps and good luck. Glad you made it to a safe place to stop.

Just For Fun · 09-06-2021, 10:20 AM

Quote:

Originally Posted by shootist

I agree it is electrical. Frame grounds at the dash, inverter, starter, chassis batteries ,engine and coach batteries. Everytime I thought I cleaned them all I would come across another. It will do it again if not found. Like the old 60s fords just quitting while driving down the road when the battery corroded up on the terminals. Clean the positive connections as well. It's most common during weather changes, hot to cold. Dry to damp etc.

We'll be limping into camp later today or tomorrow and will begin this and tightening effort.

Thanks.

96 Wideglide · 09-06-2021, 10:22 AM

Wonder if your alternator has died?

wolfe10 · 09-06-2021, 10:24 AM

I would NOT drive until you verify that everything is back working. You don't want to be stuck on the side of the road OR do expensive damage to your drivetrain.

So, pull out your wrenches and digital voltmeter and figure out what is happening.

twinboat · 09-06-2021, 10:52 AM

You have a bad alternator.

Your chassis battery volts dropped while driving. That effects the lights and transmission controller.

While running the generator you recharged your chassis battery. You have bi-directional charging.

Generator off, engine running, you should see 13+ volts on the chassis battery. There are no solenoids or relays that would prevent the alternator output from getting to the chassis battery.

If the alternator is not falling apart or the belt is loose, let your generator run and let the house charger keep the chassis battery up.

Just For Fun · 09-06-2021, 11:08 AM

All seems to be fine this morning. Everything working as it should - for now.

But with low fuel, no appropriate fueling stops in relatively close location and way too many thing to check for the failed item(s), I decided to limp home - some 40ish miles.

I do appreciate all of your inputs. I'll be keeping a close eye on all gauges and have planned for safe pull-offs along the way. Like: Walmarts and other large areas.

Please do keep you info coming.

Thanks,

wolfe10 · 09-06-2021, 11:12 AM

At least check the connections on the chassis battery!

And, make sure the chassis battery voltage is above 12.5 VDC. Easy work around is to run the generator. Your inverter/charger MAY directly charge the chassis battery bank as well as the house bank.

But, if not, use the boost switch so that charge on the house bank is "shared" with the chassis battery.

RamiDav · 09-06-2021, 12:28 PM

Sounds like a failed alternator to me.
Twinboat has figured it out.
People have completed long trips by running the gen. as long as the belt
and its accessories are turning ok.

Timaz · 09-06-2021, 02:15 PM

If your coach has one of these check it. It allows the both the house and chassis batteries to be charged by the alternator. Mine died and it stopped charging the chassis battery.

Tim

fcmcelr · 09-06-2021, 02:16 PM

Since this problem seems intermittent and you were experiencing dim headlights, it would be good to know the battery voltages of BOTH your house and chassis battery banks while you were driving when you had the problem. If they weren't both the same voltage with one bank charging and the other bank not, you likely have a big boy relay that needs to be cleaned.