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-   -   WTS light won't turn on and Bus won't start... (http://www.skoolie.net/forums/f49/wts-light-wont-turn-on-and-bus-wont-start-23683.html)

jnymdnyt 08-01-2018 01:32 PM

WTS light won't turn on and Bus won't start...
 
Before I got this bus I had ideas of cruising down the Coast but that all changed recently.

On top of trying to figure out why the bus is stuck on 2nd and reverse gear only, I recently bought and installed a new battery under the hood because it was low and wouldn't accept charge. I also borrowed an OBD1 from a friend but wasn't able to read the codes because it wouldn't connect. I also checked all of the fuses and sprayed electric parts cleaner. After turning the ignition on and off, I noticed the glow plug light wasn't turning on anymore and when I tried to start it wouldn't start. I've done some research in other forums but couldn't have an exact engine/electrical system to reference my situation.

When the bus started, it would emit White smoke that would disappear right away.

This is for a 1995 Chevy G30 Collins Super Bantam Diesel 6.5 V8 with 4L80E Transmission.

Here's what I found that sort of make sense in a diesel forum:

"The ECM mounted on the side of the engine (mine was relocated under the driver seat) is responsible for illuminating the "Wait to start" lamp. It goes through a self check when it gets a start signal from the key switch.

There are only a couple of reasons the WTS lamp takes a long time. One is the ECM is faulty and when doing its self check it will find a problem that can correct itself after several seconds. The other common problem is the ECM does not receive good 12 volt power and this may be fixed by replacing the relay in the power distribution center (fuse box) on the fender well.

If the problem is in the ECM it may eventually need to be replaced. In my opinion the ECM can become intermittent because of a part on the circuit board failing to make a good electrical connection or just changing value due to many heat/cool cycles. The ECM computer looks for nominal voltage values when it is powered up and if something is out of range will not pass the self test keeping the lamp off.

Try the relay first."

Questions:

1. How do I find out if the ECM is not working.
2. If the glow plugs are bad would that keep it for illuminating the WTS light?
3. Is there a way to start the bus even with bad glow plugs. ( I need to move it for street cleaning next week or get an $84.00 ticket).

I thought i'd give it a shot myself before calling AAA and take it to a shop.

Thank you in advance.

EastCoastCB 08-01-2018 01:46 PM

Usually the glow plugs are only for starting in the cold.
On those engines the ECM has to be relocated to make it survive. they overheat in the factory location.

My work truck has that transmission. Mine only goes into R, 1, and 3. Bad solenoids in mine. They're inside the tranny, too.

brokedown 08-01-2018 03:36 PM

Is the starter not spinning when you turn the key?

Not sure on the 6.5 but I had a 6.2 that I switched to a fully manual glow plug setup. it relied on a temperature sensor on the motor that wasn't very reliable. Hooking a button directly to the glow plug solenoid ended my glow-related problems.

If the starter isn't spinning, you may have an interlock issue, or you may just have a problem with the starter or starter solenoid. You can jump the solenoid with a screwdriver to bypass all the login upstream of the solenoid.

Similarly, you can use the same screwdriver trick on the glow plug solenoid to heat them up. My 6.2 needed glow even on hot days.

BlackJohn 08-01-2018 04:59 PM

Disconnect your batteries and remove the ECM form its location. I would imagine you will find some rust on the hold down bolts, giving it a bad or no ground. Clean that up or relocate to another area, not so damp as that gets.
An easy place to start and go from there.

Hook it back up when grounding is good and try starting.


John

jnymdnyt 08-01-2018 07:27 PM

4 Attachment(s)
Thanks to all that responded.

The starter is spinning when I turn on the key.

I am starting to suspect that the glow plug might not be the issue because it is not that cold where I am in San Francisco and because I took off the injectors and it wasn't quirting diesel, checked the pump and diesel was going in the fuel filter but not coming out. Might be something electrical connected to fuel delivery.

As far as the ECM, it was already relocated under the seat connected by 2 wire harness and is not bolted down, basically just dangling.

I've attached some pictures for reference in case someone sees something I am missing.

Don't even want to think about the transmission issue at the moment and would be happy driving in "limp mode" like I have been the past couple of months.

I am glad there is a forum like this to keep my sanity.

golfersmurf57 08-03-2018 01:24 PM

Quote:

Originally Posted by EastCoastCB (Post 283996)
Usually the glow plugs are only for starting in the cold.
On those engines the ECM has to be relocated to make it survive. they overheat in the factory location.

My work truck has that transmission. Mine only goes into R, 1, and 3. Bad solenoids in mine. They're inside the tranny, too.

Those solenoid are easily replaced. You'll see them on the valve body once you drain and drop the pan.

golfersmurf57 08-03-2018 01:49 PM

Quote:

Originally Posted by jnymdnyt (Post 283991)
Before I got this bus I had ideas of cruising down the Coast but that all changed recently.

On top of trying to figure out why the bus is stuck on 2nd and reverse gear only, I recently bought and installed a new battery under the hood because it was low and wouldn't accept charge. I also borrowed an OBD1 from a friend but wasn't able to read the codes because it wouldn't connect. I also checked all of the fuses and sprayed electric parts cleaner. After turning the ignition on and off, I noticed the glow plug light wasn't turning on anymore and when I tried to start it wouldn't start. I've done some research in other forums but couldn't have an exact engine/electrical system to reference my situation.

When the bus started, it would emit White smoke that would disappear right away.

This is for a 1995 Chevy G30 Collins Super Bantam Diesel 6.5 V8 with 4L80E Transmission.

Here's what I found that sort of make sense in a diesel forum:

"The ECM mounted on the side of the engine (mine was relocated under the driver seat) is responsible for illuminating the "Wait to start" lamp. It goes through a self check when it gets a start signal from the key switch.

There are only a couple of reasons the WTS lamp takes a long time. One is the ECM is faulty and when doing its self check it will find a problem that can correct itself after several seconds. The other common problem is the ECM does not receive good 12 volt power and this may be fixed by replacing the relay in the power distribution center (fuse box) on the fender well.

If the problem is in the ECM it may eventually need to be replaced. In my opinion the ECM can become intermittent because of a part on the circuit board failing to make a good electrical connection or just changing value due to many heat/cool cycles. The ECM computer looks for nominal voltage values when it is powered up and if something is out of range will not pass the self test keeping the lamp off.

Try the relay first."

Questions:

1. How do I find out if the ECM is not working.
2. If the glow plugs are bad would that keep it for illuminating the WTS light?
3. Is there a way to start the bus even with bad glow plugs. ( I need to move it for street cleaning next week or get an $84.00 ticket).

I thought i'd give it a shot myself before calling AAA and take it to a shop.

Thank you in advance.

I'm not familiar with the GM diesel. I will say if its computerized it takes a computer to fire each injector. I'd test all fuses marked ECM with a test light. If all are hot in on & start, you might try a jumper wire from battery pos to one of the glow plugs for about 15 seconds and crank it. Don't use starting fluid!!! If the injectors are not firing it won't run. You might find one injector terminal and read volts across it see if its pulsing your obd friend may have a noid light to visually check for pulse. Also it may have a high pressure oil pump IH Cat and the Powerstrokes do. They go bad I don't know how you removed an electronic injector without it leaking high pressure oil everywhere. If it involved just cracking a line to ck. For fuel it may be nozzle injection an there's a fuel solenoid that's off. But without having seen one no thoughts.

EastCoastCB 08-03-2018 01:54 PM

Quote:

Originally Posted by golfersmurf57 (Post 284424)
Those solenoid are easily replaced. You'll see them on the valve body once you drain and drop the pan.

Oh, nice!
Hadn't looked into it much as its not MY truck. I just drive it every day. In 1st and 3rd lol.

cadillackid 08-03-2018 03:26 PM

Quote:

Originally Posted by EastCoastCB (Post 284437)
Oh, nice!
Hadn't looked into it much as its not MY truck. I just drive it every day. In 1st and 3rd lol.


golfer is right.. the solenoids are in the valve body so you dont have to RnR.. ive also found on the 4L(80/60)E that sometimes the wires just come unplugged or the plastic connectors get brittle and crack in the constant hot trans fluid over the years..



and all it takes is for ONE of those solenoids to act wierd and the computer says 'You're gone!' and throws it to limp mode..


if the WTS light isnt turning on.. and the OBD scanner isnt even connecting, id begin to suspect the ECM or the power going to it.. I would start by measuring for +12 VDC at the pins on the ECM connectors to make sure its actually powering up all the way..

-Christopher

jnymdnyt 08-03-2018 11:20 PM

I was under the impression the when the "SERVICE ENGINE SOON" light was on the it's a sign that the ECM is working.


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