Dim Toad Lights
After getting our tow bar and brake system installed, we found that the toad lights were very dim, both the brake and turn lights. We spent several days trying various options to get this to work until victory was ours. Our “fun” on this project was enhanced by knowing we had a big vacation planned just a few days away.
- Our tow brake installer suggested first trying a heavy-duty flasher unit for the E450 chassis (a simple plug-in replacement if it would work). All we succeeded in doing was blowing a fuse. Turns out there actually isn’t a heavy-duty flasher unit available, just two different pinout versions.
- The next suggestion was to wire in a power conversion kit. This is a common add-on for pickup trucks used to pull trailers with lots of lights on them.
- We spent one afternoon wiring in a power conversion kit (a “Hoppy” - Hopkins Manufacturing). We wired the “Hoppy” into the existing LD wiring for the trailer plug except for the power, which we got from the 12V charge line that was run for the Unified Tow Brake. Got great results with the brake lights but we had no directional lights whatsoever on the Saturn.
- There was a voltage input coincident with the directional wire that goes into the “Hoppy”, but nothing comes out. We could capture an 8.2V peak voltage input while the directional is operating so either the peak wasn’t high enough to trigger the “Hoppy” or the threshold voltage is set too high on the “Hoppy”. The 8.2V does explain why the toad lights are so dim!
- The peak voltage when the brakes are applied yields 11.9V at the input to the “Hoppy”, so we know 11.9 is sufficient for the “Hoppy” to communicate to the toad, but 8.2V for the directional is not.
- We tried various additional options with the Hoppy, including having it drive all the directionals (including the LD ones) and various wire configurations to no avail. The only test which did work was to pull out one of the tail lamp bulbs on each side of the LD - not the best solution, but it showed that the number of lights being driven in the standard chassis put the base electronics at their limit.
- We decided that perhaps another brand would yield better results, so we picked up a Draw-Tite ModuLite “Lite”, #18187. It wired in exactly like the Hoppy (into the trailer harness portion along with a fused, dedicated 12V power line which we already had for the Unified Tow Brake line). One difference - Hoppy said for tow (not toad) vehicles which did not have separate brake and directional lights to cut off the brake wire input. Draw-Tite said to ground it.
- With this in place the toad lights and rig lights work GREAT, nice and bright AND we finished as the sun was setting the night before our vacation!
Pictures
Here is a picture of the Draw- Tite ModuLite “Lite” in place. Its spliced in line with the existing hitch plug wiring, just add a 12V line (we did a Tee into the 12V going to our Unified Tow Brake)
Another shot with some descriptive text
