Ignition switch wired to only start from the engine compartment

[shade-tree_pilot]

Hey skoolie friends, I've got an issue I'm hoping someone has seen before that'll save me some time with the multimeter. The district that had my bus (2003 Thomas, 3126 Cat RE) added some kind of kit that rewired the ignition switch so that the bus ONLY starts from the engine bay.

Their thinking was it would get the driver's to check the oil daily. I'd like the actual key ignition switch to work instead while retaining the ability to start the engine from the rest as well.

Anyone else seen this?

[CHEESE_WAGON]

It's likely that they simply clipped the solenoid wire at the key switch, or possibly at the starter relay / solenoid.

[shade-tree_pilot]

Originally Posted by CHEESE_WAGON

It's likely that they simply clipped the solenoid wire at the key switch, or possibly at the starter relay / solenoid.

I'll check there in the morning, thanks!

[Taz420]

Originally Posted by shade-tree_pilot

Hey skoolie friends, I've got an issue I'm hoping someone has seen before that'll save me some time with the multimeter. The district that had my bus (2003 Thomas, 3126 Cat RE) added some kind of kit that rewired the ignition switch so that the bus ONLY starts from the engine bay.

Their thinking was it would get the driver's to check the oil daily. I'd like the actual key ignition switch to work instead while retaining the ability to start the engine from the rest as well.

Anyone else seen this?

Our pushers have an "override" system to allow it to be started from the engine bay. I was under the impression that it was for the mechanic during service, nothing to do with pre-trip. There is a switch that transfers control from the key to the engine bay (labeled Control Front/Rear), a Run/Stop switch, and a Start button.

My guess is that Control switch has been permanently jumped to Rear.

[shade-tree_pilot]

Originally Posted by Taz420

Our pushers have an "override" system to allow it to be started from the engine bay. I was under the impression that it was for the mechanic during service, nothing to do with pre-trip. There is a switch that transfers control from the key to the engine bay (labeled Control Front/Rear), a Run/Stop switch, and a Start button.

My guess is that Control switch has been permanently jumped to Rear.

I haven't seen a switch like that in the bus, it's possible it may have been completely deleted when the "rear start only" modification was made. I'll keep an eye out for that override when I get to the "electrical" phase of the build. I feel pretty lucky, the factory harness has easy-to-read labels printed on absolutely everything and is very well put together.

[Taz420]

Originally Posted by shade-tree_pilot

I haven't seen a switch like that in the bus, it's possible it may have been completely deleted when the "rear start only" modification was made. I'll keep an eye out for that override when I get to the "electrical" phase of the build. I feel pretty lucky, the factory harness has easy-to-read labels printed on absolutely everything and is very well put together.

It's in the back, under the "hood" at the top center of the engine bay. I can take pictures of what we have on monday after AM route, maybe at least get you pointed in the right direction. But the factory system basically has the switches on a metal panel mounted at the top of the engine bay. There's also a switch for the engine bay light right there. If you take that panel down I would assume it's in the same wiring harness as the run/stop switch and start button. Being as these are current district buses I can't actually open anything up or take anything apart for a better look though.

[shade-tree_pilot]

Originally Posted by Taz420

It's in the back, under the "hood" at the top center of the engine bay. I can take pictures of what we have on monday after AM route, maybe at least get you pointed in the right direction. But the factory system basically has the switches on a metal panel mounted at the top of the engine bay. There's also a switch for the engine bay light right there. If you take that panel down I would assume it's in the same wiring harness as the run/stop switch and start button. Being as these are current district buses I can't actually open anything up or take anything apart for a better look though.

Awesome, thanks, I'll give that a look on Monday or Tuesday when I get back over to the bus and report back. Thanks again!

[Taz420]

Originally Posted by shade-tree_pilot

Awesome, thanks, I'll give that a look on Monday or Tuesday when I get back over to the bus and report back. Thanks again!

Another thought I had, It's entirely possible that there is just something wrong with the key switch, and the district may have simply said "screw it, the bus is on short time, we're not putting any more money into it, just start it from the back" lol.


It just seems very odd to me that they would intentionally force drivers to start their buses from the back. It seems like an unnecessary safety hazard because what if the neutral start safety switch malfunctioned and the spring brakes weren't holding too well (or like we just had one where a dash valve went bad in the middle of a route and didnt dump the air at all so didnt allow the spring brakes to set)? If you park on level ground you might never know that happened..You push the start button and the bus runs away from you. Thats why you always cover the brake when you crank the engine.. You also have the belts right there in front of you that could grab loose clothing or long hair.. it just doesn't make sense.

[shade-tree_pilot]

Originally Posted by Taz420

Another thought I had, It's entirely possible that there is just something wrong with the key switch, and the district may have simply said "screw it, the bus is on short time, we're not putting any more money into it, just start it from the back" lol.


It just seems very odd to me that they would intentionally force drivers to start their buses from the back. It seems like an unnecessary safety hazard because what if the neutral start safety switch malfunctioned and the spring brakes weren't holding too well (or like we just had one where a dash valve went bad in the middle of a route and didnt dump the air at all so didnt allow the spring brakes to set)? If you park on level ground you might never know that happened..You push the start button and the bus runs away from you. Thats why you always cover the brake when you crank the engine.. You also have the belts right there in front of you that could grab loose clothing or long hair.. it just doesn't make sense.

That's a good point; it does seem like more of a hazard. I was also wondering how the rear switch is igniting the glow plugs before cranking since it's only a temporary on switch.

I'll take my multimeter and check the ignition switch itself. I've noticed that when I turn the switch with the key it feels like it's got some slop between the different positions and I've been looking for a replacement. I can also hear a relay clicking in the fuse box by the door. I'll check to make sure it's not blown as well.

[Taz420]

The pushers were all out today when I got off route, and I think they will be tomorrow too. I have an activity trip Wednesday so I'll take some pics then when I pretrip.

[Taz420]

Here you go. This one has the control transfer and Run/Stop in one switch (Front is the key, Off is Stop, Rear is Run).

[shade-tree_pilot]

Originally Posted by Taz420

Here you go. This one has the control transfer and Run/Stop in one switch (Front is the key, Off is Stop, Rear is Run).

I didn't notice anything like that switch the last time I was working on it but I can see there's some aftermarket wiring going into the panel and a cover where another switch would fit. I'll open it up and have a look next time I'm working on it. Thanks for the help, I really appreciate it

[CHEESE_WAGON]

Chances are, it's a factory-made jumper plug for the purpose and all you have to do is install the proper switch in the factory position for its purpose, remove the jumper plug and connect the switch.

[Matencio]

Originally Posted by shade-tree_pilot

Hey skoolie friends, I've got an issue I'm hoping someone has seen before that'll save me some time with the multimeter. The district that had my bus (2003 Thomas, 3126 Cat RE) added some kind of kit that rewired the ignition switch so that the bus ONLY starts from the engine bay.

Their thinking was it would get the driver's to check the oil daily. I'd like the actual key ignition switch to work instead while retaining the ability to start the engine from the rest as well.

Anyone else seen this?

I know this post is a few years old but I'll add input here for the sake of it in case someone buys an MC9 or 102 A, B, C et al from Greyhound or any fleet bus from a school board.

I used to drive for Greyhound before the big strike (1989). We had three switches that had to be turned on before the bus would start. We didn't have keys for obvious reasons. Theft was a big concern so the company set up the three switch system. The battery compartment had a lever that had to be lifted up (think breaker box with a lever), the rear had a switch like shown below, and then an unlabeled push button on the dashboard that had to be held down until the bus started up. My guess is the school board has done something similar. Create a jumper wire and see if that starts the motor up, if so, then wire in a key switch and your set. Add in a separate kill switch that is hidden just because. And that push button could be held down while the bus was in gear so we could drive the bus off the highway even if the engine died. How cool was that? I know, right? I used it a few times.

[Taz420]

Originally Posted by Matencio

I know this post is a few years old but I'll add input here for the sake of it in case someone buys an MC9 or 102 A, B, C et al from Greyhound or any fleet bus from a school board.

I used to drive for Greyhound before the big strike (1989). We had three switches that had to be turned on before the bus would start. We didn't have keys for obvious reasons. Theft was a big concern so the company set up the three switch system. The battery compartment had a lever that had to be lifted up (think breaker box with a lever), the rear had a switch like shown below, and then an unlabeled push button on the dashboard that had to be held down until the bus started up. My guess is the school board has done something similar. Create a jumper wire and see if that starts the motor up, if so, then wire in a key switch and your set. Add in a separate kill switch that is hidden just because. And that push button could be held down while the bus was in gear so we could drive the bus off the highway even if the engine died. How cool was that? I know, right? I used it a few times.

Lol did we go through a time warp??? It's not a few years old lol, he just posted it last week!

But yeah I still think he has something that failed and the district just didn't want to repair it, so they just started it from the back. I have serious doubts that this was an intentional modification - I stand by the safety concerns as my reasoning for that. If he can hear the relay clicking it's probably not the ignition switch as I originally thought, could be a burned relay contact or rotten socket.

Even what Greyhoud did was just a master battery switch (which some of our buses do have, we shut them off over weekends and vacations due to mystery/gremlin drains), a kill switch in the back, and the dash start switch. You still start it from the driver's seat.

[flattracker]

Hello,
Crown busses come with similar setups. My first crown has a key switch in the engine bay for engine starting. My "new" Crown has a switch in the engine bay for operating the engine.

[Meathead]

Originally Posted by shade-tree_pilot

Hey skoolie friends, I've got an issue I'm hoping someone has seen before that'll save me some time with the multimeter. The district that had my bus (2003 Thomas, 3126 Cat RE) added some kind of kit that rewired the ignition switch so that the bus ONLY starts from the engine bay.

Their thinking was it would get the driver's to check the oil daily. I'd like the actual key ignition switch to work instead while retaining the ability to start the engine from the rest as well.

Anyone else seen this?

I have a 2001 Hdx Thomas and this is how it works;

Your bus came from the factory with a vandalock system.The front key switch checks to see if all the hatches, doors and windows are closed and latched, or the bus will not start. You should also hear buzzers going off if just one hatch is open.

The rear start button will start the bus no matter what door or hatch is open. Mechanics don’t necessarily need to be concerned for child safety.

I suspect that your vandalock system has been compromised and the school system didn’t want to deal with it. Maybe they couldn’t track down the hatch/window causing the bus not to start. Maybe they pulled the buzzers and figured that the old bus can be started from the back until we get rid of it.

So here is what you do. Run a wire from the “st” terminal on your keyswitch to the button in the back. You have now bypassed the vandalock system and you are effectively pushing the rear button from the front.

Many of us have done this. I was given this tip after I aggressively gutted my bus and it would not start.
It seems you are in the same spot. You just took a different route.

Other than your keyswitch being broken, this is your problem.

Peace

[Taz420]

Originally Posted by Meathead

I have a 2001 Hdx Thomas and this is how it works;

Your bus came from the factory with a vandalock system.The front key switch checks to see if all the hatches, doors and windows are closed and latched, or the bus will not start. You should also hear buzzers going off if just one hatch is open.

The rear start button will start the bus no matter what door or hatch is open. Mechanics don’t necessarily need to be concerned for child safety.

I suspect that your vandalock system has been compromised and the school system didn’t want to deal with it. Maybe they couldn’t track down the hatch/window causing the bus not to start. Maybe they pulled the buzzers and figured that the old bus can be started from the back until we get rid of it.

So here is what you do. Run a wire from the “st” terminal on your keyswitch to the button in the back. You have now bypassed the vandalock system and you are effectively pushing the rear button from the front.

Many of us have done this. I was given this tip after I aggressively gutted my bus and it would not start.
It seems you are in the same spot. You just took a different route.

Other than your keyswitch being broken, this is your problem.

Peace

Looking at the diagram for the Vandalock system its lockout relay interrupts the line between the key and starter relay when engaged. OP is hearing the relay click when he turns the key to start, so I'm thinking it's something else.

[Meathead]

There are 5 -6 start relays in the system on boards 1-4. #4 being the one in the dash. Mine was clicking also.

[Meathead]

OP,
Did you ever figure it out? I had that problem AND I made things worse by crossing wires somehow and blowing the fuse to the ecm. We never found the fuse. Searching the internet, lots of ppl have trouble finding the fuse. We ended up running a new wire from the ignition switch on the “box “ in the back.