Advanced Electrical Diagnostics Needed M1078

[Lugnuts]

The Basic Question is what happens when you turn your master switch on and off? I know this is going to bring out bizarre replies but hear me, please. My problem is random shut down of battery power, both 12vdc and 24vdc. If it shuts down momentarily while it is running it will stay running and transmission gets a little funky on shifting. Codes 1212 and 1213 come up which is low and high power. I am assuming that is a good indication of loss off battery and I am running off of alternator. This only happens when the truck is at operating temperature seemingly for a period of time. (Remember Random) The really annoying part of this is when it does it and you do shut it down it will not restart until cold which would indicate and electrical part hot and working when it cools. What I mean by it won't restart is that when you turn the Master Switch on everything lights up then you push the start button it engages the solenoid momentarily and all systems shut down and then will come back momentarily. OK I can hear the screams "It's your batteries or connections". Well they have been thoroughly been done and I won't argue you but they have even been reshaped and load tested to ensure positive connection.
Now I have the Military Troubleshooting but they don't show me a schematic or systems schematics so I don't really know what happens when you turn the battery master on. I have seen the Battery Shunts and then I saw an Electromagnetic Switch of good size in the area of the shunts and my lights went on that this is suspect but I don't know if this is the problem because I haven't heard mention of it in troubleshooting at all.
I really need the experienced ONES to enlighten me! Magic Wand probe type thing if you please and it will be greatly appreciated. I am willing to compensate for good and correct advice. Thank you, Lugnuts

 

[tennmogger]

When power is dropping out as you describe, start at the battery with a voltmeter and work your way toward the starter, and toward the Polarity Protection box and Power Distribution panel, looking for the point beyond which there is no DC voltage (applies to 12v and 24v circuits). Even though you have checked, it sure sounds like a high resistance connection under load.

 

[Suprman]

I would replace all the relays and reseat all the breakers. I see alot of trucks have bad main grounds. I always run a new big ground from the batt negative to the main frame rail. Make sure its sanded for good contact. Check the starter connections and all the extra grounds.

 

[NDT]

As usual we need to know what year model your truck is. Do you have LBCD? Have you done the diagnostics on the CE Niehoff website?

 

[Ronmar]

Yep, what truck model. Could be a bad DC connection or bad ground. Could be a LBCD on an A1 truck or a polarity box on an A0. Could be a main relay or even a main switch or any of the associated wiring. The not restarting till cool is a great clue and can also be a valuable troubleshooting tool, depending on the truck year and model...

 

[coachgeo]

Another thing to consider in trouble shooting in relevance to not starting till it is "cooled" is a TIME coincidence. The time it takes engine to cool off might also be enough time for something else that is not engine temperature related to happen.

 

[Lugnuts]

When power is dropping out as you describe, start at the battery with a voltmeter and work your way toward the starter, and toward the Polarity Protection box and Power Distribution panel, looking for the point beyond which there is no DC voltage (applies to 12v and 24v circuits). Even though you have checked, it sure sounds like a high resistance connection under load.

I agree. Can you explain to me what the boxes are under the air cleaner and spare tire area. I have seen the shunt but the other box has 4 wires on it. Are there more connections elsewhere in the line or are there just the 2? And what is the shunt for? Thank you

 

[Lugnuts]

As usual we need to know what year model your truck is. Do you have LBCD? Have you done the diagnostics on the CE Niehoff website?

Didn't know that Niehoff had diagnostics. What is an LBCD? And the year I don't know. Should that be on the dash? Thank you for your reply

 

[Lugnuts]

I would replace all the relays and reseat all the breakers. I see alot of trucks have bad main grounds. I always run a new big ground from the batt negative to the main frame rail. Make sure its sanded for good contact. Check the starter connections and all the extra grounds.

All done. Thank you for your reply

 

[Lugnuts]

Yep, what truck model. Could be a bad DC connection or bad ground. Could be a LBCD on an A1 truck or a polarity box on an A0. Could be a main relay or even a main switch or any of the associated wiring. The not restarting till cool is a great clue and can also be a valuable troubleshooting tool, depending on the truck year and model...

I will obtain the information. I am not familiar with LBCD? These boxes you speak of, are they located under the spare tire/ air cleaner area? Thanks for the reply

 

[Lugnuts]

When power is dropping out as you describe, start at the battery with a voltmeter and work your way toward the starter, and toward the Polarity Protection box and Power Distribution panel, looking for the point beyond which there is no DC voltage (applies to 12v and 24v circuits). Even though you have checked, it sure sounds like a high resistance connection under load.

This is what I am not familiar with and why a schematic would be appreciated. The battery connections going to the starter are straight off the battery/ both positive and ground. There are 2 boxes under the spare tire/ air cleaner that I know nothing about. Could and would you explain, please and thank you

 

[Ronmar]

I will obtain the information. I am not familiar with LBCD? These boxes you speak of, are they located under the spare tire/ air cleaner area? Thanks for the reply

Well the box could be a polarity protection box, thats why we need the year and model as it will tell us what schematic to look at to give you troubleshooting tips. If the box is between the tire and the air cleaner and about in the middle of the vehicle, that may be the polarity box. But the polarity box has 4 terminals with 6 wires attached to it. two go to the battery, two come from the alternator and to go to the power distribution panel... that could be one of the problems with a bad connection or a bad diode.

The shunt is part of the STE wiring which stands for standardized test equipment. Its sense lines go to a large cannon plug by your left knee when driving. It is in line with the starter ground and I assume it is to test how much current the start circuit is pulling to diagnose starter and or battery issues along with crank RPM... not used unless you have STE test kit...

 

[Lugnuts]

Well the box could be a polarity protection box, thats why we need the year and model as it will tell us what schematic to look at to give you troubleshooting tips. If the box is between the tire and the air cleaner and about in the middle of the vehicle, that may be the polarity box. But the polarity box has 4 terminals with 6 wires attached to it. two go to the battery, two come from the alternator and to go to the power distribution panel... that could be one of the problems with a bad connection or a bad diode.

The shunt is part of the STE wiring which stands for standardized test equipment. Its sense lines go to a large cannon plug by your left knee when driving. It is in line with the starter ground and I assume it is to test how much current the start circuit is pulling to diagnose starter and or battery issues along with crank RPM... not used unless you have STE test kit...

Thank you for your help. I will get that information today. I plan on cleaning all those connections and studs and to test if anyone of those boxes turn on and off with the Master Rocker Switch. When I have the problem happen it is a clean break in power and not a resistance in connection. It definitely breaks a connection.

 

[mechanicjim]

the LBCD , Load and battery control device, basically its a diode box with capacitors, it protects via diodes from reverse polarity(hooking battery up backwards) it also senses system/battery voltage. should the battery voltage drop below a certain value during engine operation it will send a signal to battery disconnect switch to disconnect the batteries. it then will act as a "simulated battery" via capacitors while also trickle charging the batteries via a small wire. once battery voltage comes back up it sends signal to reconnect batteries.
In commercial vehicles they have load shed devices that turn off the loads to keep the batteries up, military went the other way as they would rather keep critical systems running for a time.
the following troubleshooting documents have pictures of what a LBCD is so you can better identify if your truck has one.

https://www.ceniehoff.com/Documents/Ctrl_Hyperlink/TG53B_uid1252012258102.pdf

https://www.ceniehoff.com/Documents/Ctrl_Hyperlink/TG0014D_uid12172009224052.pdf

 

[coachgeo]

the LBCD , Load and battery control device, basically its a ...

best description offered to date of this unit

 

[Ronmar]

Yep, the LBCD(circled in red) is only on the A1 and as mentioned senses battery voltage and load and controls the load disconnect relays(circled in green) Via,the other connections/wires.

The A0 polarity protection box only has the large diodes, 4 terminals and just the 6 large cables connected to it. It also doesn't have the disconnect relays circled in green or the manual disconnect between the relays and batteries... this is a pic of an A1 schematic.

 

[Lugnuts]

the LBCD , Load and battery control device, basically its a diode box with capacitors, it protects via diodes from reverse polarity(hooking battery up backwards) it also senses system/battery voltage. should the battery voltage drop below a certain value during engine operation it will send a signal to battery disconnect switch to disconnect the batteries. it then will act as a "simulated battery" via capacitors while also trickle charging the batteries via a small wire. once battery voltage comes back up it sends signal to reconnect batteries.
In commercial vehicles they have load shed devices that turn off the loads to keep the batteries up, military went the other way as they would rather keep critical systems running for a time.
the following troubleshooting documents have pictures of what a LBCD is so you can better identify if your truck has one.

https://www.ceniehoff.com/Documents/Ctrl_Hyperlink/TG53B_uid1252012258102.pdf

https://www.ceniehoff.com/Documents/Ctrl_Hyperlink/TG0014D_uid12172009224052.pdf

Most helpful thank you. I went to work on it today and found I have a Polarity Protect Device a little different than the one you showed me

 

[Lugnuts]

Most helpful thank you. I went to work on it today and found I have a Polarity Protect Device a little different than the one you showed me

You mentioned battery disconnects. Where might they be located? They must be electric if the device can disconnect the batteries.

 

[Lugnuts]

As usual we need to know what year model your truck is. Do you have LBCD? Have you done the diagnostics on the CE Niehoff website?

Manaufacture 10/97. I have a Polarity Protect Device bu Sure Power/ MSN 19207-12420932/ I had another person that showed me what the Low Battery Control Device was and it didn't look like that. I am asking if my device took the place of the other and if not what is the location of the other? Thanks for the help

 

[Lugnuts]

I will obtain the information. I am not familiar with LBCD? These boxes you speak of, are they located under the spare tire/ air cleaner area? Thanks for the reply

10/97 Polarity Protection Device MSN 19207-12420932/ Are there more boxes elsewhere? Thanks for your time