320d quick tatch not working

[Steel Horse]

Quick tatch works when power is supplied by a 12 v battery directly to actuator motor. I have replaced both relays and checked all fues in panel below relays, all good. I have continuity at wires that connect to actuator. I'm getting 12.8 volt when switch is toggled in both directions, but when I connect wires back to actuator, nothing??
Any suggestions would be greatly appreciated. Thanks

 

[ahart]

If you lose voltage when the load is connected to the circuit but have it when disconnected, typically means there is a nearly broken wire or weak connection. Pivot points on harness routing are a good place to start, otherwise you’ll have to follow the harness back to the source. Remember, a DMM set on ohms only needs 1 strand of wire to show continuity, same when set on volts, only one strand required to show 12 volts.

 

[Nige]

I have continuity at wires that connect to actuator.

What @ahart said above. If you checked continuity with a DMM then it may pay you to repeat the test using a 5A test light connected to Batt+ at one end and with the other end connected to frame ground. If a wire will pass that sort of current it should work under load.

 

[Steel Horse]

If you lose voltage when the load is connected to the circuit but have it when disconnected, typically means there is a nearly broken wire or weak connection. Pivot points on harness routing are a good place to start, otherwise you’ll have to follow the harness back to the source. Remember, a DMM set on ohms only needs 1 strand of wire to show continuity, same when set on volts, only one strand required to show 12 volts.

Thanks ahart, kind of what I figured. Just trying to rule everything out before I start pulling wire out to expose it. Outside of the 2 relays, is there any inline fuse that may have blown. And is it possible that the toggle switch may be bad?

 

[Steel Horse]

Just want to thank both of you for sharing your wisdom concerning this matter. Great education
I did find the problem. There is an inline 20 amp metal fuse relay down by the starter. I pulled it out to check resistance and it was showing good, but went up to NAPA and got another Just to be sure.
Thankfully that resolved my issue. Everything is working properly.
Thanks again for your help!

 

[skyking1]

good of you to post back.

 

[Steel Horse]

FYI. Update from July with pictures.

The quick tach actuator stopped functioning and kept blowing the fuse a few weeks ago. After troubleshooting, I discovered that the wiring harness connected to the actuator on the backside of the frame was exposed and unprotected.
The wiring is fixed and cannot be replaced, and the cut in the conduit is too far down to repair.
I temporarily resolved the issue with silicone and heat shrink, but it did not last long.

I had to purchase a new harness from John Deere for $577.40, only to find the same design error.
Another sales rep walked by and said, wow we sale a lot of those... I spoke with service and they confirmed it was a bad design.

Many others have encountered this issue, so I hope this fix helps. I filled the conduit with silicone and wrapped the wires with 3/8-inch braided hose to protect them from the sharp edges of the conduit. I then secured all wiring and connectors to the actuator with zip ties to minimize movement.

 

[Steel Horse]

Quick tacht resolved