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Only getting 4.8 volts at the coil

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  #1  
Old 06-08-2019, 11:57 AM
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Default Only getting 4.8 volts at the coil

Having this problem that's been annoying me for the past few days now. I've been having no success in getting my 2001 Electra Glide Resurrection projected started. I have a jump box hooked up to my battery and been stressed out on the fact that the bike only turns over, but won't start. All of the fuses and relays are good. All of the other electrical devices are working as they should. There's no fire whatsoever is getting to the plugs, but I see fuel misting from the exhaust. At least I know that the injectors are firing. Finally took out the volt tester and confirmed that I'm only getting 4.8 volts from the coil lead.

Anyone have any suggestions at what could be causing such low voltage at the connector??? I'm ready to start riding...
Any help will be greatly appreciated.

Mike
 
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Old 06-09-2019, 07:46 AM
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pull the source lead from the coil.
jump coil terminal direct to battery and see if it will start, if so, follow ign circuit. bad connections can reduce voltage as well as broken wires internal to the insulation.
measure voltage on the source to the coil open ended. should be battery voltage.
if it does not start with the jumper, look toward the module. the module provides ground path for the coil and if it is shorted, voltage will pull down.
always check ground connections, strange things happen. however, loss of ground should not pull down source.
 
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Old 06-09-2019, 09:44 AM
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Thanks bustert. I labeled everything before I removed the wiring from the original frame, just to be sure that I knew where they were supposed to go once I swapped everything over into the replacement frame. I do have 1 connector under the fairing that doesn't have anyting connected to it, so I just assumed that it was for the CB or 2-way walkie-talkie between the driver and the passenger.

The bike did take a good amount of damage near the timing cover, where the foot board was pushed up into the timing cover eventhough it didn't crack the cover. Do you think that the impact could have damaged the ignition module inside?
 
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Old 06-09-2019, 08:32 PM
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Bad fuel pump relay or broken wire but you really need to tell us if its EFI or carbed.
 
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Old 06-10-2019, 07:50 PM
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if your machine uses the cam sensor, the wiring does run underside in that area and maybe the wreck caused some damage to it. i think the crank sensor wire is underside also.
do not over look a bad bar switch.
you may need to get an electrical schematic to trace voltage source end to end which you can get from the hd sip portal.
i have the 2001 electrical book but it is not very clear for a free hand approach, relies on having a breakout box.
have you tried to reseat the plugs on the remote ign module?
KISS it first and keep track of what you did and do one thing at a time, that way you know what fixed it.

https://serviceinfo.harley-davidson.com/sip/index
 

Last edited by bustert; 06-10-2019 at 08:05 PM.
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Old 06-20-2019, 06:48 PM
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My bad Max Headflow. My bike is fuel injected.

At first I couldn't get the fuel pump to prime at all, but once I pulled all of the circuit breakers and saw all of the corrosion on them I took them all apart and cleaned the connections on all of the breakers.

Now the pump is priming.
I have the battery ground wire connected back to the transmission, where it was originally.
I haven't looked at the wires that run underneath the frame. I'll check it in the morning.
I have all grounds wires on the replacement frame connected back to where they were on the original frame.
I did connect my test light to the ground and I received 12v at the Pink wire, 7.8v on the red/white wire, and 0 volts on the black/white wire.


Thanks for all of the advice.

Mike
 

Last edited by olkarz; 06-20-2019 at 06:49 PM. Reason: Correct spelling
  #7  
Old 06-21-2019, 06:42 PM
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Here are some pictures of the things that I checked today:

I took off the timing cover and I didn't see the ignition module that others have on their Electra Glide Fuel Injected bikes on videos all over YouTube. It's making me think that this isn't the correct motor for a 2001 Electra Glide Classic Fuel Injected.
This looks like a camshaft position sensor, because it connects to the crankshaft position sensor on the left side front of the motor.



Here are some pictures of connectors that aren't connected to anything and their locations. I don't remember any of these connectors being connected to anything when I removed this engine from the original frame.
My friend that has a '98 Road King says that this connector is connect a battery tender to trickle charge the AGM battery without having to remove the seat. It is located directly underneath the seat, behind the ECM.




I believe that this connector is for the Harely-Davidson Tech's diagnostic tool, since it is located right next to the ECM. I could be wrong, but I don't recall that it was connected to anything.



These 2 pictures are of a connector that had this rubber dust boot covering the plug when I removed the wiring harness from the original frame. I don't know what the wire colors mean, but they are different than the 3 that is connected to the coil plug.


Y'all notice the blue tape that I used to label every wire and the places where they belong, before removing the wiring harness from the original frame.


The picture above and the 1 below are inside of the Batwing. 1 of them goes to the radio and none of my friends that ride Harleys knows what the other plug is for.


I believe that this 1 is the connector to the HD radio. It was damaged in the front end damage of the original front forks. But I could be mixing up the 2 connectors in these 2 picture.

I did scrape off all of the rust from the ground point on the frame, where the grounding wire connects from the front of the frame to the triple trees.

Needless to say I still can't get anything more that 4.8v to the red/white striped wire on the coil connector. At this point.... I'm STUCK! I'm either going to have to find a Harley Tech to come look at the bike, in my friend's shop or put on my BIG BOY tighitie-whities and just take the bike to the HD Dealership and just swallow whatever they charge me to get it running. I'm too close to the end of the project to just give up.

Any help that any of you can provide will be greatly appreciated.

Thanks
Mike
 

Last edited by olkarz; 06-21-2019 at 06:47 PM. Reason: Correct spelling
  #8  
Old 06-21-2019, 08:41 PM
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Did you measure the voltage going in and out of the fuel pump relay?
 
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Old 06-24-2019, 09:01 AM
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Max Head I'm getting 5.4v at the fuel pump connector wire yellow with green stripe.

At the fuel pump relay, when I hit the switch I'm getting 12v then it drops to 9.7v, but I'm still only getting 4.8v at the coil connector.

I swapped the fuel pump relay connector to the relay right beside it but no changes.

Is there some type of immobilizer circuit that's built into the ECM that would deactivate the coil or pump when a accident is sensed? I'm stuck know. Other than slicing the cover on the whole harness under the tank and checking each and every wire.
 

Last edited by olkarz; 06-24-2019 at 10:20 AM. Reason: Additional detail added
  #10  
Old 06-24-2019, 12:21 PM
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Max Head I'm getting 5.4v at the fuel pump connector wire yellow with green stripe.

At the fuel pump relay, when I hit the switch I'm getting 12v then it drops to 9.7v, but I'm still only getting 4.8v at the coil connector.

I swapped the fuel pump relay connector to the relay right beside it but no changes.

Is there some type of immobilizer circuit that's built into the ECM that would deactivate the coil or pump when a accident is sensed? I'm stuck know. Other than slicing the cover on the whole harness under the tank and checking each and every wire.
At this point I need a diagnostic tool to see what code the ECM is recording.
 


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