# Neutral safety switch location for Allison MD3060



## garceau

Help. I have a 1993 Vectra with the MD3060 6-speed Allison. The key will not always start or engage the starter.  I replaced the ignition switch and had a new solenoid installed on the starter and had it tested. 

When it doesn't start, I get no power to the solenoid. (The small wire from ignition) I believe it is the neutral safety switch. Where is it located and can I do the job. I do most of my own work.  And on this engine and transmission, could I bypass the switch. Any help would be greatly appreciated. 

garceau


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## Guest

RE: Neutral safety switch location for Allison MD3060

The neutral safety switch should be located on the trans ,, it is also the back up light switch ,, u can bypass it but it may make the backup lights stay on ...
 Let me know what u find


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## garceau

RE: Neutral safety switch location for Allison MD3060

Ok, thanks for the reply. But where on the trans. This is a automatic 6-Speed World Allison. I see what I think is the RPM sensor and then there are a lot of wires going to either one large or two close together plugs with a lot of wires. The plug(s)  are on the the drivers' side above the ID plate. This is the push button shift with the DP. 

Thanks for any help you can give
garceau


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## Guest

RE: Neutral safety switch location for Allison MD3060

May i ask this ?? is u'r panel flashing???
If so u have codes that need ot be cked out ,, if not then we go from here ...
the wires and stuff u seen on the opiside of the speed sensor should be the piece u are looking for ,, but i would ck with alison on this prob ,, since there has been some issues with the trans ,,,
BTY do u have level jacks ,, i assume u may have ,, they can also play a big part in this picture ,, JMO ..
If u can give me the nubers off the trans ,, i can make a few calls Tomorrow and find out ,,,  :approve:


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## garceau

RE: Neutral safety switch location for Allison MD3060


 Hey 730. I think I have my answer. A local Allison man called me and said this: there is no neutral safety switch on this transmission. It is located in the ECU. 

Iâ€™m to check the gray plug, pin #6, Wire #123 for power when it fails to crank. If it is the ECU, they can get expensive. (Do you know about how much?) 

 He also said I had the W3 transmission and for that year, they had the W2 & W3. 

What he could not help me with is where the 123 wire goes to after it leaves the ECU. That would be up to Winnebago. He said there might be a relay somewhere that is causing my problem and that if I get power but no cranking; that might be the case. Do you know of a relay on the 1993 Winnebago Vectra, WSM35RQ ?

Thanks loads, you guys are super. I wish I had found you years ago. 

garceau


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## Guest

RE: Neutral safety switch location for Allison MD3060

I'm not sure about u'r ECU ,, but i did put one on a 98 class a the other day and it ran ,, my cost ,, $500 ,, i did not mark it up due to the fact that the customer had already shelled out over 300 on the stuff that didn't fix it ,, and bty is was the engine ecu that i replaced on this unit ,, allison did have a relay that cuased some shifting probs ,, but i never heard of a no start prob ,,, i would call u'r local allison dealer and see what they have to say ,, try to talk to one of the shop's forman ,, cause he has more knowledge then do the service writers ,,
let us know back on u'r findings


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## jimmie diesel 24

RE: Neutral safety switch location for Allison MD3060

I saw your posting about your vectra. I have a 1993 vectra with the same problem. Have you found your problem? I have found the relays  that are in the ecm.
It is under the dash. There is a relay for the neutral safety. I have changed it  but it did not help. When it don't crank  I wait and I hear the relay buzz and then it will start. I thank it my be a ground problem but it has been too cool to work on it. Have U found any wire diagrams for  the md3060?  thanks.
Jimmie Cummings


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## H2H1

Re: Neutral safety switch location for Allison MD3060

hey Jimmie welcome to the forum. very good info you provided to a fellow RVer. I am sure with your and Rod help he and you will get your problem fixed. Yes it been to cold to do anything lately but spring is coming


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## Guest

Re: Neutral safety switch location for Allison MD3060

Agree .. Hollis on the cold ,, but i sure hope the OP post us back on the find ,, i would really like to know  :approve:  :approve:  :approve:


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## dbarton291

Re: Neutral safety switch location for Allison MD3060

There is no neutral start switch on any Allison World Trans.  Garceau:  Your Allison guy has it right.  When ignition is turned on, and the shift selector initializes in neutral, the ECU puts power on 123.  123 connects to one side of the coil of the neutral start relay located somewhere in the vehicle.  If 123 is not powered, could be the selector or its wiring, or it could be the ECU.  Don't forget to check for deformed or corroded terminals on ECU and shift selector connectors.

If the ECU is putting power on 123, could be the relay contacts or coil are going intermittent, or there are deformed terminals in the harness, an intermittent in the ignition lock, or the starter solenoid is going batty, etc. etc. The key is to trace the circuit step by step.  The hard part often is getting the vehicle manufacturer's wiring schematic and finding out where each piece of hardware is located.


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## garceau

Re: Neutral safety switch location for Allison MD3060


 Ok guys. Thanks for the input. I did find the neutral safety switch relay in the box under the dash. I had more trouble getting the cover plate screws off then anything else. 

I could feel it click when it worked or not when it didnâ€™t. I bought a new relay from NAPA and installed it. Still same problem. 

I called the Allison shop and asked if it would hurt anything to bypass the relay. He said no, saying it was an extra safety device. But he added that he could only suggest doing that as an emergency action. He did say that there was no way that the trans would be in gear when the engine was not running. 

 I removed the cover on the old relay and closed the contact points and plugged it back in. 

It has fired every time and there is no hesitation. It seems to be starting stronger than it has in the last ten years. I know this is not the correct fix but it works for me. Maybe one of you can tell me which other relay might be causing the intermittent failure. 

Ernie

Allegro1@juno.com


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## cmick50

RE: Neutral safety switch location for Allison MD3060

Hello, I have a 1993 euro premier with the md3060 6 speed transmission I have t he same problem with the coach not starting but my touch pad won't light up. If i keep trying to start it the touch pad will try to light up if i try long enough it will start but won't go in gear . i've had people tell me the transmission ECU is bad but i don't want to buy one until i'm sure they cost around 2300.00 anyone with any ideas     thanks  Bruce


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## Ryan W

jimmie diesel 24 said:


> RE: Neutral safety switch location for Allison MD3060
> 
> I saw your posting about your vectra. I have a 1993 vectra with the same problem. Have you found your problem? I have found the relays  that are in the ecm.
> It is under the dash. There is a relay for the neutral safety. I have changed it  but it did not help. When it don't crank  I wait and I hear the relay buzz and then it will start. I thank it my be a ground problem but it has been too cool to work on it. Have U found any wire diagrams for  the md3060?  thanks.
> Jimmie Cummings


Did you ever figure out this issue, turn key on, no start, wait till relay buzzes and then starts?


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## jimmie diesel 24

jimmie diesel 24 said:


> RE: Neutral safety switch location for Allison MD3060
> 
> I saw your posting about your vectra. I have a 1993 vectra with the same problem. Have you found your problem? I have found the relays  that are in the ecm.
> It is under the dash. There is a relay for the neutral safety. I have changed it  but it did not help. When it don't crank  I wait and I hear the relay buzz and then it will start. I thank it my be a ground problem but it has been too cool to work on it. Have U found any wire diagrams for  the md3060?  thanks.
> Jimmie Cummings


Had to have a new transmission ECM. About $2000. works fine now.


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