Dead shift control pad

[profo]

Been trouble shooting like crazy tracked wires and followed tm my shift keypad selector does not do anything traced wires and tm said it was keypad defective, so I changed the keypad and still nothing anybody has anyone come across this before, all grounds good, power good and all breakers are fine! It's a wtec3 with md3070 transmission in a m1078A1.

 

[NDT]

Send both your ECUs to Transmissioninstruments.com for a free checkout. You could have two bad ECUs.

 

[profo]

Send both your ECUs to Transmissioninstruments.com for a free checkout. You could have two bad ECUs.

Thanks I was wondering if there was someone that checks out the brains parts so at least your not running in circles!

 

[profo]

Found this today and it goes straight into trouble shooting and easy to read!!

Allison WTECII & WTECIII ECU's [TCM's] Power Failure Troubleshooting Guide​

​

​

The following procedures are technical, and should not be attempted if you are unfamiliar with electronics or uncomfortable working with electrical components. You do so at your own risk.
Have You recently replaced or charge the battery outside the vehicle? If Yes, recheck connections in Your battery compartment and look for two 10 gauge wires, near the battery terminals, which supplies positive and negative power directly to Your ECU through VIM [Vehicle Interface Module]. The VIM contains two fuses [for ECU only] and up to six relays powered by the ECU [ including the start relay ].

Recommended tools : Assemble 12V/15-25W light bulb [spare brake lamp bulb or similar, #1156,#1073 etc.] with 20 gauge solid copper wire [ ordinary Hookup or "Bell wire" ]. Sstrip 1/2" on test side. When You check ECU connectors, lamp must glow bright white light: A Dim light will indicate a bad connection somewhere, likely due to oxidization. Voltmeter will not indicate bad connections. An ordinary volt meter or VOM isnt reliable for this test, however you will need one to check the lower voltage systems.
After assembly, check lamp directly on Your battery terminals. Caution, lamp will become HOT !!!
Always disconnect the battery or turn off the battery switch [Power Train Battery] prior to disconnecting or connecting back ECU connectors!

Instructions for WTECII system [ two digits on Your shift selector ]

For 1992;1993;1994 and early 1995 models and experience erratic or no display, especially when is cold weather or seen some codes, please log to http://www.rvshifters.com for more information. Have You seen code 69-32 already? Stop troubleshooting = 100% defective ECU!!!
Locate the ECU [ in most RV's ECU is mounted directly to the shiftpad ]. If remote selector is used, ECU maybe nearby, close to VIM Module or, mostly on Trucks, close to transmission [ just follow bundle of wires from transmission ].
Disconnect the battery first, then unplug two oval shape ECU connectors and reconnect the battery. Check the connector with black plastic [ another is white ], rear side, for numbers.
Only 8 numbers from 34 are imprinted [ both sides of the row ]. Insert test lamp leads into corresponding connector sockets:9 and 2 then 18 and 11.
Next turn "ON" Ignition switch and insert test leads to 9 and 12. #9;#18 = BATTERY GROUND; #2;#11 = BATERY POWER; #12 = IGNITION
If lamp is bright, ECU is probably defective unless is defective display itself [ 1% chance ]. There is no practical method to check display on the vehicle except to swap selector from another vehicle. But, if you do have a remote shift selector, you can check display using ordinary 9V battery and hookup wire. Just remove two fuses from Vehicle Interface Module and connect the 9V battery using Bell wire slightly bent on ends, so they can hold inside connector sockets. Minus terminal to #9 and positive terminal to #2 and #12. After few seconds remote shift selector should start beeping and show on display " cat eyes ". Just be sure You do have a good connection with wires and sockets.
If display comes "ON", ECU is defective.

Instructions for WTECIII system [ single red digit on Your shift selector ]
Have You recently replaced battery and accidentally swapped battery terminals? If "YES", ECU maybe fried beyond repair. If "NOT", locate the ECU (in most RV's is near shift selector, close to VIM Module or, mostly on Trucks, close to transmission - just follow bundle of wires from transmission). Disconnect the battery first, then unplug all three connectors from ECU and reconnect battery. Closely check the GRAY connector for numbers. Insert test lamp leads into corresponding connector sockets: 1 and 32 then 16 and 17.
Next turn "ON" Ignition switch and insert test leads to 17 and 26. If cavity #26 is blank, use BLACK connector socket #4. Lamp must glow brightly.

#17; #32 = BATTERY GROUND; #1; #16 = BATERY POWER; #26 gray or #4 black = IGNITION

Next turn ignition and battery "OFF", reconnect GRAY ECU connector only, then reconnect battery and turn "ON" ignition. Then very carefully touch gold plated pins #16 and #32 [ on ECU for BLACK connector ] with lamp test leads. Lamp must glow bright. Then use a Voltmeter to check 5V on pin #3 [ on ECU for BLACK connector ] against chassis ground. DO NOT use test lamp!!! If no 5V is found on pin #3, ECU is defective.
Also check socket #3 on BLACK connector with Ohmmeter against chassis ground. Must be Must be over 4k ohms.
Shift selector can be check using ordinary 9V battery and hookup wire. Connect the 9V battery using hookup wire, which you may have to slightly bent on the ends so they can hold inside BLACK connector sockets. Connect Minus terminal to #32 and positive terminal to #3 and #16. After power "UP" all segments and RED LED [ Mode ] will be illuminated for 8 second and then display will show " cat eyes ". If one pushbutton "D","N" or "R" is hold down during power "UP", display will show "d", "N" or "R" for 2 second only. This way, You can check pushbutton switches.
If display will not be illuminated, maybe defective shift selector or harness. To check out harness, You must disconnect connector located
1/2' from selector. Then remove strain relief [black plastics ] from on vehicle harness connector and check closely rear side for letters.
"P" = GROUND "R" = POWER "N" = SENSOR POWER
Insert 3 short lengths of hookup wire into sockets "P", "R" and "N" and use a voltmeter to check voltage between "P" and "R" and between "P" and "N" if You using 9V battery. If ECU and battery still connected, insert lamp leads to "P" and "R", then turn ignition "ON" and with voltmeter check for 5V in socket "N". If You do have voltage and there is no display, shift selector is most likely defective. If You do have voltage on ECU pins and not on the shifter connector, a defective harness is indicated.
Check continuity with Your Ohmmeter between "P" and chassis ground. Should be less than 1 OHM. If the meter reads "open", (Infinate resistance) find a good ground in the cabin, cut "P" wire 3" from connector and reconnect with new ground. If missing 12V - "R", found "ignition" power, cut "R" and reconnect with "ignition" power. If missing "N" [ 5v ], cut "N" and reconnect with "ignition" power.
12V will not damage the shift selector. If one of three last steps will power up the shift selector but no response to commands, You may have additional harness damage or defective ECU or shifter. In this case, You can send ECU + shifter for free testing [You pay for shipping only].

Home​

​

​

 

[Jakelc15]

Need to check power and ground at keypad connector

 

[73m819]

Issues like this that can happen ANYTIME and more likely to happen on the side of the road at dark 30, about as far away from the home base as you can get IS WHY I love the lmtv truck series so much.

 

[Suprman]

A lot of the 3126 A1 trucks have bad solder joints on the breaker relay board. Causes all kinds of issues. Relays go bad over time they should all be replaced. The Allison stuff is very reliable and is widely used. I have seen bad cab to trans harnesses though. Make sure the ecm is plugged in properly it's behind the passenger kick panel.

 

[profo]

Keith knight let me use his spare ecu and It worked, I had trouble shot using the above info I posted and determined it was the ecu I think the GP PERSONAL tryed jumping the truck incorrectly because in the video it show the key pad displaying neutral before they started it or it went bad between here and there! Either way it's up and working now! Just gotta find a ecu so I can give back Keith's spare unless he says he wants to sell this one! Any way thank you Keith for all the help! Will also send mine to transmission instruments to see if can be repaired.

 

[coachgeo]

Out of Just a hunch..... for shiatz and Grinz of it, remove Keith's and put your's back in and see what happens......

 

[profo]

Out of Just a hunch..... for shiatz and Grinz of it, remove Keith's and put your's back in and see what happens......

tryed it still dead puppy!

sending to trans instruments!

Marty

 

[scottmandu]

I had the same issue, it was a bad TCM.

 

[snowtrac nome]

mine had the same problem there is a 6 relay pack behind the panel under the fuse relay box mine was missing likely no power to the tcm. one of those relays would have to power up the tcm try relay pack replacement

 

[profo]

mine had the same problem there is a 6 relay pack behind the panel under the fuse relay box mine was missing likely no power to the tcm. one of those relays would have to power up the tcm try relay pack replacement

I confirmed it was the ecu I replaced the ecu with a loaner and everything works, I need to try to find a transmission ecu used somewhere!