Turbo HC Electrical Problem

[zak_62]

Hello everybody:
Yesterday when I try to start my esprit, I let the fuel pump pumps for about 5 seconds and turn the key to ignition. The start crank once and the dash turns completely black.
I tried to read the battery off the multimeter, it still reads 12volts, and if I wire the car up with my battery charger, the lights on the dash will come back on. Seems like that I have a weak battery, but the battery is brand new that I replaced two weeks ago because my old one is getting weak on me.
I had the car sitting for a roughly 1 week or so.

What would you suggest that I should check on first?
Thanks
Isaac

[wedg1e]

Could well be a bad earth connection to the battery, ie chassis/ engine earthing.
Might then be that your original battery wasn't as bad as you thought...

Ian

[95LOTUS]

If you can get the battery charged to the point where you can get her to start, check the battery voltage with the engine running. If you're seeing about 12V, then the alternator is the likely culprit (you should see about 14V if the alternator is working). It helps if you check it with a decent load...try it with the high-beams on.

Alternatively (no pun intended ), if you can charge the battery, and it's losing it's charge within a week, then something must be on and draining the battery like a radar detector or the stereo, or a light. I bought a new battery last year thinking the old one, which was less than a year old, had lost it. When the new one exhibited the same problem, I finally realized that the lights in the boot were always on, which is how I discovered what that little switch next to the engine shroud was for, and had been laying on the carpeting all those weeks. Needless to say, I'll NEVER forget what that little switch is for!

Hope this helps!
Bill
'95 S4S

[zak_62]

Yeah, Good call, let me go check all the lights.

[zak_62]

Is it normal to read a small amount of resistance, 50000 Ohms, across the two primary battery connectors after I disconnected the battery and the accessories attaching to the positive side??

[lotusguy]

Hi,

First Rule of Thumb with Esprit Electrical Problems = Grounding. There just aren't many good grounding points on these, or any plastic car. Problems with ground account for 99% of all electrical problems. Good Luck! Happy Motoring!... Jim'85TE

[turbo_hc]

This may be as simple as a battery connection - when I have tried to start mine in the past the connection is ok for lights/auxillerys etc but when a large current is needed ie for start then the battery terminal connection arcs and fails - I'd check these first!!

Jimbo

[95LOTUS]

zak_62 said:

Is it normal to read a small amount of resistance, 50000 Ohms, across the two primary battery connectors after I disconnected the battery and the accessories attaching to the positive side??

If I follow you correctly, you're measuring the resistance across the 2 leads going to the battery, without the battery in the circuit. I'm not sure what you're going to see, but I would expect it to be difficult to measure (wildly varying readings) since any electronic devices left in the circuit (such as the memory backup for the stereo, ECU, ABS, airbags, etc.) have capacitors on the 12V line that would interfere with measuring the resistance since they will hold a charge.

Even if the 50Kohm reading is correct, that's still less than a milli-amp load, and wouldn't be enough to discharge the battery in a couple of weeks.

If possible, you might try putting an ammeter in series with the battery with everything you can think of turned off (including the engine ) to see if there's a reasonable current sink that could be discharging the battery. If so, start pulling fuses until you nail down the root cause.

Bill
'95 S4S