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The trailer brake controller on my 96 f250 is telling me I have an open ground. I know it’s on my truck because I plugged another vehicle into the trailer and had no issues. I have a single ground wire running from the controller all the way back to the plug. The plug is grounded to the frame also. Any ideas on what else could be causing this problem?
The trailer brake controller on my 96 f250 is telling me I have an open ground. I know it’s on my truck because I plugged another vehicle into the trailer and had no issues. I have a single ground wire running from the controller all the way back to the plug. The plug is grounded to the frame also. Any ideas on what else could be causing this problem?
do you have any other things grounded to the same spots? and what is the condition of your frame to battery ground? You should have a daisy chained negative cable that goes to the frame. this gets bad. Run a dedicated one or clean up the oem one
I have a few things grounded to that spot. I have already ran a dedicated ground to the back. The ground for brake controller and trailer plug are using the same bolt. There is another thing grounded with this bolt but I’m not sure what the third is, it is a spot that was grounded stock. The frame in that spot was cleaned up using brake clean and a wire brush before putting them all back on this spot. I have bypassed the daisy chaining of the oem grounding.
I have a few things grounded to that spot. I have already ran a dedicated ground to the back. The ground for brake controller and trailer plug are using the same bolt. There is another thing grounded with this bolt but I’m not sure what the third is, it is a spot that was grounded stock. The frame in that spot was cleaned up using brake clean and a wire brush before putting them all back on this spot. I have bypassed the daisy chaining of the oem grounding.
can you get your DVOM out and measure the two points of your new grounded setup bypassing the stock daisy chain so one lead on your negative terminal and then one on your frame ground point.
To be clear, youre saying your stock battery to starter cable no Longer goes there, but you have a dedicated cable to the frame to the battery?
If so, then after the first DVOM check, what do you get?
Then, turn on the key and turn on the headlights, then to the same thing. If you can , get a longer alligator clip wire and find your brake controller ground spot and use the battery negative and do the same check
If you are having fun, go ahead and scratch the alternator case a bit with a brush then do the battery to the case of the alternator while not running and while running. skip if not having fun
I mustve misunderstood the wire you were talking about orignially. The photo below is the daisy chaining I was meaning. The ground seen in that photo does not go to the brake controller.
I mustve misunderstood the wire you were talking about orignially. The photo below is the daisy chaining I was meaning. The ground seen in that photo does not go to the brake controller.
Ill take a better look this weekend.
so ultimately, the reason i was curious about your frame ground is the one on the back of the frame where your trailer plug is , should be to the frame of the truck. then your trailer brakes are on your trailer, that trailer should have grounds for the brakes (to the axle/trailer) by virtue of being mounted to that, then there should be a ground that is shared to the truck and the trailer plug so that the power your battery is sending it can be returned via the ground.
THen your frame to battery is the weak point in this mix if your trailer is in good shape and your rear frame ground is good. The trailer controller isnt going to need that large of a ground id not think, but it of course still needs to be. The factory frame ground is a pretty weak/insufficient unshielded strap that goes into the negative battery cable on its way to the starter. its kinda stupid how bad that was of an idea.
I was finally able to get around to spending some time on this and I added a wire from the battery straight to the frame and it is working as it should now. Thanks for the help.
