dim lights on popup

[86subaru]

the lights on my popup are real dim and blinkers flash slow, on the 97 legacy L awd a/t 2.2 motor, when i hook it up to another car there fine, also the lights on the 97 are fine, thinking it could be a ground problem ? any easy fix , going to haul it today, no plug on the legacy had splice into the wiring ,thanks

[unverviking]

Another tell tale sign of a bad ground issue is if you were to have the Right Turn Signal on , and you could see very slight blinking in the left side as well.

 

Did you use one of those univeral modules that combine the turn and brake into 1 for the trailer ?? If so, did you run a 12volt line in to it from the battery ?? The one that I installed earlier this year needed a 12volt into it, along with the left turn, right turn, and brake. Working fine.

[86subaru]

yes , got it from etrailer,

[Cougar]

To see if there is a grounding problem you can measure the difference between the two grounds using a voltmeter. You may need to make a long jumper wire to do the measurement. Just measure the voltage between two known good ground points on the car and the trailer with the lights on. A good connection will show no voltage difference.

[86subaru]

ok, thanks

[unverviking]

To see if there is a grounding problem you can measure the difference between the two grounds using a voltmeter. You may need to make a long jumper wire to do the measurement. Just measure the voltage between two known good ground points on the car and the trailer with the lights on. A good connection will show no voltage difference.

 

Someting I thought of on this... Wouldn't a continuity check (on most volt meters) show a 0 if you were to check between both grounding points ?? Because you're checking from end to end on the wire... Then wouldn't a check on any metal point on both the trailer and car be a 0 in order for the ground to be truly connected ??

 

I'll have to try this next time I think about it, and have mine hooked up.

[Cougar]

You are correct. A truely good connection between two points should be zero ohms. This applies to a grounding system and to the power side of the circuit. You just need to make sure power is disconnected from the circuit whenever measuring the resistance of a circuit. The meter applies its own power to the circuit when measuring resistance and if other current is flowing also it can change the true reading and possibly damage the meter.

 

In reality, you may possibly see a couple of ohms of resistance between the car and the trailer grounds due to wire losses. The method I gave to measure the circuit is for a voltage drop that will occur due to resistance between the points measured, if there is a connection problem. Current needs to be flowing through the loads when using this method so the voltage losses will appear across the bad connections due to the current flowing through the extra resistance.