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valleybusman
Top Member

USA
798 Posts

Posted - 05/19/2016 :  9:11:34 PM  Show Profile  Send valleybusman an AOL message  Reply with Quote
I have a 2004 International with EGR . A few weeks back bus died along freeway on a late trip back . When I got there the transmission indicator showed the number 8 . Odd for a 5 speed . Engine wouldn't turn over .Had to two bus back to yard . Next morning I hooked up my laptop and had a bad ICP . Replaced the ICP and removed battery cables and cleared the transmission . Now after that the driver would tell me bus would buck and water in fuel light came on went off . Tonight I was radioed this bus was dead in the middle of the road .I took my laptop and a bus and went up . I told driver to take bus and drop his kids off . I will stay and get bus running . If I can't get it going he could pick me up and back to the garage .I tried to start bus . No starter . I check cables and they are fine . I plug my laptop in and turn key on . Showed no power too the IDM and ECM . The little plugs in the bottom right corner were apart . So while I sat waiting for my ride back . Checked again and the plugs came together and bus started up . When I get back to the garage my laptop says I have 626 code and M reset .What am I looking at and where should I start ? Thanks

RonF
Top Member

867 Posts

Posted - 05/20/2016 :  03:33:23 AM  Show Profile  Reply with Quote
626 is and unexpected reset fault. If I recall correctly this is a power or ground issue to the ECM. Check the ECM clean power harness in the battery box, all of its connections and fuses. Follow that harness from the batteries to the ECM. Check the ECM power relay as well. Look for loose connection and or melted plastic, corroded connections along the way.

US Army retired CMBT
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valleybusman
Top Member

USA
798 Posts

Posted - 05/20/2016 :  07:30:51 AM  Show Profile  Send valleybusman an AOL message  Reply with Quote
Ron would this cause the the starter to not work ? A few weeks ago I replace the the cable and wire in the box for the ECM .
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RonF
Top Member

867 Posts

Posted - 05/20/2016 :  08:35:36 AM  Show Profile  Reply with Quote
Not usually however your problem may be right here.

" The little plugs in the bottom right corner were apart . So while I sat waiting for my ride back . Checked again and the plugs came together and bus started up ."

US Army retired CMBT
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valleybusman
Top Member

USA
798 Posts

Posted - 05/20/2016 :  4:30:36 PM  Show Profile  Send valleybusman an AOL message  Reply with Quote
Thought I would fill you in . Today I got bus started no problem . Decided to check relays . they were fine . I put those back and put relays back . Bus wouldn't even turn over . Computer couldn't connect . Checked voltages with my power probe . 2.6 volts at all the relays for starter and ECM . After awhile I got 12.5 volts reinstalled relay .Bus wouldn't start . Checked again 2.6 volts . So Monday check wires where should I start battery box or ECM
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second.flood
Top Member

USA
640 Posts

Posted - 05/22/2016 :  06:30:51 AM  Show Profile  Reply with Quote
There is a positive cable junction on the fire wall under the hood. Make sure the two nuts are tight on the studs. Actually put a socket on them.
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57fan
Senior Member

United States
148 Posts

Posted - 05/22/2016 :  7:11:53 PM  Show Profile  Reply with Quote
Valley, We need more information to assist you. We know you are working on a 2004 DT-466EGR engine but what model bus are we referring to, CE, FE or RE?

As for the 626 Code RonF has it correct. You are checking for Battery voltage to both relays I am assuming. You should have Battery Voltage to both relays and to 2 terminals on the IDM relay. Depending on what model bus you are working on you will find that many of the same wiring connection and locations are the same between models. (If your laptop is connecting to the ECM then you have power thru the relays and to the ECM)

An easy way to tell if your ECM is powering up is listen for the SRA (turbo actuator) to move with key on and off. If you do not hear it then that is a indicator of a ECM power issue. The ECM gets key on signal from the key switch and the start circuit goes thru the ECM as well. So if the ECM has no power then the starter will not turn over (ECM controls the starter relay). Also the IDM will not power up since its relay is controlled by the ECM as well.

Start at the battery box and check all connections. Leave the key in the on position and wiggle all the connectors and listen for the SRA to move (wiggle test). Do not over look the condition of the terminals in the ECM and IDM relay sockets. (the parts are available from RWC) We recently had a bus die on the road 5 times and could not find the cause. I replaced the relay socket, terminal and wires to the socket and issue is gone. Hope this helps and pleas provide more information on what bus you are dealing with.

Lead, Follow or get out of the way! Thomas Paine
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valleybusman
Top Member

USA
798 Posts

Posted - 05/23/2016 :  08:31:19 AM  Show Profile  Send valleybusman an AOL message  Reply with Quote
I am working on a RE . When I turn the key on no noises from engine . Nothing .I show low voltage to the starter and ECM relay . I checked connections at battery good and the wire that exits the box showed 12.5 volts .When I bypass wires from the battery and supply power to the relays . Things make noise and bu will start .

Edited by - valleybusman on 05/23/2016 08:31:58 AM
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57fan
Senior Member

United States
148 Posts

Posted - 05/23/2016 :  7:10:24 PM  Show Profile  Reply with Quote
Start at the batteries check connections and condition of wires. If I remember right there is 2 fuses that lead to a connector (both should have battery voltage). then they head towards the rear control box / panel. There is a connector in between the box and the previous connector. there is a connector for all the wires to go into the box and then directly to both relays. pretty straight forward but this is an IC. If you bypass all of this then it is definitely a power / wiring issue. Keep us informed in what you find.

Lead, Follow or get out of the way! Thomas Paine
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valleybusman
Top Member

USA
798 Posts

Posted - 05/25/2016 :  1:54:39 PM  Show Profile  Send valleybusman an AOL message  Reply with Quote
Okay I have some more info and am not sure why ? I checked the relay terminals again . I show 12.5 volts on all except one . As soon as I turn the key on they drop to 2.6 volts . Why ???
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57fan
Senior Member

United States
148 Posts

Posted - 05/28/2016 :  11:52:13 PM  Show Profile  Reply with Quote
Valleybusman. Do all of the circuits drop to 2.6V or just one circuit. You should have B+ on pins 30 and 86 on the relay. When the ignition (key) is turned on then the ECM grounds (internally) the wire on pin 85, energizing the coil in the relay and latching the circuit to pin 87 and sending B+ to the ECM. If you try and measure the voltage on pin 86 then you are trying to measure a ground voltage. I have seen the same results with a DVOM. You should see B+ on pins 30 and 87. If the voltage drops to 2.6V on pins 30 and 86 then you have other issues. Check all your wiring connections and wires. Look closely at the relay connections and relays are cheap. Put in a new relay to test the circuit.

do you have Service manual S08297 for the bus? You can find a diagram on page 83.

Do you have a relay test kit? There are many kits out there where you can check voltages without back probing the wiring. LISLE tools makes a kit for under $50.00 and it works well. If you have sealed relays like the CE, BE and FE use then you need to cut off the sealed portion of the relay to use it.

Let us know how it goes.

Lead, Follow or get out of the way! Thomas Paine
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valleybusman
Top Member

USA
798 Posts

Posted - 06/09/2016 :  10:50:31 AM  Show Profile  Send valleybusman an AOL message  Reply with Quote
I checked relays and they were fine .I would get the 2.6 volts when I would turn the key to start . I figured it was a wiring problem that supplied power to the relays so I rewired the relays . Now everything works
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