| Author |
 Topic  |
|
|
DanHan
New Member
5 Posts |
 Posted - 03/21/2019 : 2:09:41 PM
|
Hello, My name is Daniel. I deal in Buses. And I have one that is traumatizing me.
It is a 2002 FE DT466 Cab-Over Flat Front School Bus w/Air Brakes, Push Button Shift MD3060 Transmission
First the Tranny was giving me a code 'D13500', Power Interruption. And I found and fixed a loose power wire to the TCM. Fixed that...
Then it would not shift. I found the motion/speed sensor on the back side of the 3060 to have frayed twisted wires that were shorting. Fixed that. Now it shifts much better.
BUT THE REAL KILLER is the that this bus quits with no notice. And usually after 1-5 miles and in traffic. It restarts after 10 minutes or two hours. And it has good power.
I replaced the ECM and I bypassed the in-line fuse in the battery box to the ECM. After that it Ran for 45 miles. I was so excited. Then it quit again and again and again.
It feels like an electrical shut down. Could a plugged fuel line be causing the fuel pressure to drop, causing the ECM to electrically shut down instead of jerking and hesitating like a normal bus not getting enough fuel?
The ECM power line from the battery must go through a relay to the ECM. Or else there would be constant power setting on the ECM. I am trying to trace the wire, but you know grease, dirt, and freeway traffic rolling by my feet sticking out from under the bus.
I left the bus at a storage facility since I had another 300 miles to drive and no wits to do so.
WHY,,,, can't I just tag the ECM power line from the relay? to the power post on the starter?
Why can't I tie the ground wire straight to the engine block?
This would cut down on the linear footage of the Ground and Power wire to the battery, saving the voltage drops and interrupts from corroded wires and connections. Every time those batteries are pulled out the wires are shifted around, sometimes pinched, jerked and twisted.
When I go back, I am taking some gauges to monitor the Fuel and ICP pressures.
I could tap into the fuel SUPPLY and RETURN lines. And run them to a barrel of clean fuel.
I could pay a backhoe to bury it.
Advice Please. Thanks Daniel Hanson |
Edited by - DanHan on 03/21/2019 7:27:45 PM
|
|
|
krmvcs
Advanced Member
362 Posts |
Posted - 03/21/2019 : 2:31:07 PM
|
Any codes? Is it just the engine shutting down or electrical power lost all together?
I had a 2000 Amtran RE with a DT466E with the same symptoms this morning and found the connector to the IPR was loose. |
-Ken- |
 |
|
|
eddo
Advanced Member
USA
311 Posts |
Posted - 03/21/2019 : 2:46:03 PM
|
I echo the question about codes. If ECM power is being lost, that should toss a code.
What quite often won't toss a code is a Cam Position Sensor- and will cause the exact symptoms you state. You can pull the sensor out (It is on the front cover of the engine, on the alternator side. Sometimes it will have rub marks on it if it wasn't spaced properly last time it was replaced- if it is scuffed, cracked, or any other damage- I would replace it and see what happens. |
|
|
|
DanHan
New Member
5 Posts |
Posted - 03/21/2019 : 7:48:44 PM
|
This is me, Daniel.
I did replace the cam sensor when I first had the problem with the TCM power interruptions. Although I did not gap it. I was on the side of the road. And I could only reach around and feel the Cam Sensor to change it. This is a cab-over with access to the forward engine from inside. I didn't seem to make a difference. But given time and daylight, I can gap it with grease when I go back. Usually when bad cam sensors have stopped my me, the bus was down until changing it. But I have read that CMP's can also present intermittent problems.
Thank you for the advice. I will put a new one in and gap it. I would very much like to know where is the power relay for the ECM 12 Volt feed. I could bypass it with a temporary toggle switch in the cab to see if I can keep it running.
I would also like to tie a voltage meter onto the 5 Volt logic voltage.I am guessing that there is only one 5 volt power supply in the system going to the sensors.
I appreciate all the help. |
|
|
|
DanHan
New Member
5 Posts |
Posted - 03/21/2019 : 7:57:31 PM
|
Sorry, forgot to reply about the codes. I got different codes from the blinking lights. And they kept changing. I will look for the notes.
Could someone direct me to a You Tube or site on reading the codes and what they mean.
And is there a wiring schematic somewhere online. Still thinking about the ECM relay.
Thank you, Daniel Hanson |
|
|
|
peter2019
Senior Member
125 Posts |
Posted - 03/22/2019 : 05:45:23 AM
|
| Here is how ECM wiring for DT466: on top of battery box, there is 3 wiring connector, two of them are 40A inline fuse for IDM and ECM, one 10A inline fuse for transmission, make sure unplug one 40A fuse to see, if bus shows" check electrical system" and doesnot even crank, that's for ECM, the wiring runs under bus from driver side up to fire wall to ECM relay, you can simply test which relay is for ECM, unplug the fuse for ECM which you already knew, the relay pin 30 should not have power any more, the wiring comes out from ECM relay(pin 87) goes to ECM and 12 pin connector, hope it help. |
|
|
| |
Topic |
|
|
|
2002 FE International Bus w/DT466 Shuts Down
