1999 Chevrolet Suburban, Erratic Speedometer Caused by Burnt Battery Terminal

This 1999 Chevrolet Suburban came in with the complaint of an erratic speedometer. I have seen this problem before, so I went straight to the positive battery cable connections. This is what I found. At first the cables look a little corroded but not too bad.

A closer look shows heavy corrosion on the terminal along with heat damage to the red protective terminal boot.

The battery terminal with the molded boot looked pretty bad from the underside.

I removed the lead spacer from the battery terminal. I did have to use a pair of pliers to remove it.

Then a razor blade to remove the rubber ring portion of the red boot.

Normally, a little clean up and a new boot, that will slide over the remaining red rubber is all that is needed. However this terminal was badly damaged.

I cut off the old terminal. Stripped and cleaned the inner cable core with a wire brush. Used my pliers to fold over the tabs on the new terminal. A little work to make sure the connection was clean and tight. Although I do not own a factory crimping tool for this step, I have never had a problem doing it this way.

I heated and soldered the crimp connection to seal the already good mechanical crimp. In case you did not know it, solder by itself makes a fairly lousy connection. Its job is to seal and strengthen, an already good mechanical connection.

After the soldering job was complete and cooled down, I folded over the tabs for the insulation. Those tabs are there for strain relief.

A new bolt, lead spacer, dielectric grease and protective red boot and this one was done. To order battery bolts and spacers, please click here.

It was very surprising to me that the customer never had a problem, with cranking this vehicle. This business is full of strange things though. I guess that is what makes it interesting to me.

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