Corolla battery/alternator ?? - Surrey_Scientist

have a slightly srange (or perhaps obvious to those in the know) problem with my corolla 1994 1.6GLi 16v EFI

A couple of times this week when trying to start , when I turn the ignition the dashboard lights go dim, as if the battery is flat, by as soon as i touch the throttle - before the engine has fired the dashboard lights go bright and it turns over and fires instantly.

Then drives OK and starts perfectly the next time....

I am therefore suspecting the battery and or alternator.

I don't have low charge lights on when I am driving.

If I use a voltmeter to test the battery :-

(A) Do I need to disconnect the leads from the terminals first

(B) what voltage should Iexpect across the terminals (no load)

To test the alternator

(A) How do I get the test-leads onto the output, as there seems to be just a multiuplug connection - do I have to disconnect this or is there a terminal exposed somewhere I can get the probe/croc-clips of the voltmeter on to ?

(B) again what kind of voltage should I expect, and is there anyway of testing under load etc. by switching various things on ...

Corolla battery/alternator ?? - Saltrampen
As an ex owner of a 1.6 GLi 93 Corolla, when my Battery went, the charge indicator light on the Battery was dark, then it would always take several more turns than normal to fire up. Topping up the battery fluid gave it a few months more life. From memory I believe it is 13.8 - 14.4 v across terminals with alternator charging the battery, but it should state this in a Haynes manual.
Touching the throttle before engine has fired up? Only thing that springs to mind is a loose or damp connection under the dash board.
If the alternator was failing to provide sufficient voltage, then the dash battery warning light stays on.
If your battery was weak, you normally hear it in the starter motor, taking more turns or making more of a laboured sound when starting.
What about the dash light dial /rheostat is that sticky in any way?
I have a Corolla Haynes manual I can refer to if you do not have one. (will look at 2night)

Corolla battery/alternator ?? - Robin the Technician
I think that the problem could be the engine earth. The movement of the throttle could indicate the earth is being sent through the cable. just disconnect, clean and refit. It costs nothing to do this first (always do the free checks first).

These are the views of Robin the Technician with 35 years in the trade. I fix, therefore I am...

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