Thread: Low amperage draw on battery.

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I posted earlier that my engine wouldn't start. I have a brand new battery with a full charge. I, for reasons listed in the other post, was testing my TPS and MAP sensors. The plugs while disconnected showed a good supply and ground from the ECM. When hooked up neither sensor was responsive. The TPS signal voltage did not vary with throttle movement. The MAP signal did not vary with load applied by a vacuum pump. I had replaced the TPS earlier this week so I really think something is up with the electrical harness. What happens to the signal after each component? Is the problem on the recieving end of the ECM?

I turned everything off and pulled the battery ground. I hooked up a test light between the ground wire and the battery terminal. The test light filament would barely glow for about a half second and die. I break the connection and reconnect and it all happens again. There is a 5amp draw on the battery that dies off until the circuit is broken and recharges itself almost like a capacitor. I would like to start pulling fuses and such with the test light hooked up but the light wont stay on long enough.............any thoughts? Maybe the clock?
Chris

When you say your engine wouldn't start do you mean the starter will not crank or that the engine will not fire? I would go back to basics and pull all fuses from unrelated circuits (lighting, radio, etc.) one at a time to isolate the failure. Was the last time the car was running before you played with the sensors? You may have damaged the harness...not likely however. Good luck

jc

jc