#6. Where else is grounding a common problem?
Here are a few specific problem spots where bad grounding is common.
A. Grounding a latch solenoid inside the door just isn’t enough. A door is a separate body part that connects to the chassis through the door hinges. Those hinges are either well lubricated, which is not good for electrical conductivity, or they’re rusty, which is just as bad. To get good electrical flow, parts that are to be attached to a door, hood, deck lid, etc. must be grounded back to the chassis or the part itself must be grounded back to the chassis.
B. Remember that the ring terminal under-the-bolt is not the only ground connection in the circuit. If you “bolt” to a body panel, that panel must be properly connected (grounded) to the chassis and the chassis must be connected to the battery (-) post. ALL CIRCUITS must start at the battery and end at the battery. Each connection in that chain has the potential to be bad, add resistance and cause a problem.
C. Many of these connections are different metals. That is, the ring terminal is probably tinned brass, the body panel is steel and the bolt is galvanized (zinc) steel or stainless. In the presence of moisture (it’s everywhere!, it’s everywhere!) different metals in contact with each other are more likely to corrode - not just rust - each material can oxidize which is an electrical no-no.
D. Watch out for ground connections where grease and dirt are common like around the starter, where the block is grounded, etc. External tooth or internal tooth lock washers are a good addition to connections in these locations, but don't use more than one lock washer as that will defeat the purpose.
E. "Everything worked fine before I sent it to the paint shop." We've heard that refrain many times. Painters like to remove ground connections so they can get a good paint finish (it's hard to mask around a ground connection). If they remember to reconnect it, they often don't remove that fresh paint so as to get a good metal-to-metal contact. Without that contact, the electricity won't flow. The connection looks great but works terrible. Go back after painting and check all of the connections.
#7. So do I need to take every connection apart periodically and clean it up?
That’s not a bad idea! But you only need to do it once if you add some dielectric grease to the connection the next time you clean it and put it together (or the first time you do it). Dielectric, or non-conductive, grease protects the joint from corrosion. You can get some from most electrical supply houses (the AC electrical kind) and a number of car suppliers sell it, too. A little goes a long way so a small tube can do a whole car with some left over.
To conclude our discussion about grounding: for any circuit to work properly, the electrical flow has to go from the battery - through the circuit - and back to the battery making a full circuit. Every component, connection, wire... everything in that circuit, must allow the flow of electrons with minimum resistance. Bad grounding is the #1 electrical problem in older cars.
Steve Watson, Watson's StreetWorks, http://www.watsons-streetworks.com
this is a good one for the solenoid steve. also make sure you have fully charged battery when testing a newly installed system. just went through this with a k-9 deployment system. after installing it we were testing it and the door would not release all the way. after checking all connections and such we found that if the car was running it was fine. after charging battery properly everything was great.
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