20th century man with '95 ISUZU Trooper LS -- still learning, must ask

BonzaiDuck

Lifer
Jun 30, 2004
15,705
1,449
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I and a friend from high-school -- we're 70 years old now -- were making a monthly recycling run with old TVs, cyber-junk and UPS batteries. The friend had some five large tube-type TVs that roommates had left when he was strapped and renting rooms. We were recycling one monthly, and we were down to the two smallest, even as the bigger of them was still a PITA. Bad decision 1: bringing the Trooper instead of the Nissan truck. Bad decision 2: discarding two TV sets in one month and using the ISUZU. Bad decision 3: assuming the big TV was stable in the back of the SUV, after insufficient testing.

Down the drive-way, over the gutter and "CRUNCH!" The large driver-side rear window in the SUZU looked like huge grains of sand held together with smoke-tinted window film. Window repair will be completed tomorrow, but the 2-week delay is another story to tell. To proceed: that rear window also has a defroster filament-- little brown conductors, all connecting on left and right to a + and - connection to the wiring harness.

I've noticed that the alarm LED on the console blinks furiously now, even after removing the battery and charging it up -- yet another story and no need for it here. I always leave the alarm button OFF, and the LED flashes briefly with the door open, but it used to go OFF in travel.

I ran the car by my mechanic for advice -- first about the window (solved), and then again about the LED. He told me "nothing to bother with. Just leave it alone. It's not going to drain the battery, and people will look in the car and decide the alarm system is armed." I thought about it, and imagined a possibility that there is a continuity sensor in the onboard computer that might cause the LED to flash like that if the rear window was broken. Asked the mechanic -- "Naw!"

WHICH IS IT? From my descriptions, is there any more insight? Would the mechanic be wrong? I have the shop and overhaul manual, but need a while to find it, and I'm even wondering if I can find indications within it. I have too much other stuff to read now. . . .

THANKS
 

mindless1

Diamond Member
Aug 11, 2001
8,046
1,442
126
This topic should probably be moved to the garage forum.

If the mechanic can't fix it or at least tell you exactly what's going on, I would ignore his "naw" and also question the battery drain.

Without knowing if the vehicle has a battery saver circuit, I don't know what phantom power draw should be on an short term test, but I would disconnect the positive battery lead WHILE keeping a multimeter connected to positive and the battery terminal (so the circuit is never broken, in case there is a battery saver circuit that you don't want to wake up and get a false/high reading from) in current measurement mode, and then see how much current is drawn with vehicle off, all doors/lights/etc off. I'd start out with a multimeter range that handles more than 400mA then switch to the lower mA range once you verify it is under that. It would be easy for it to be operating normally and start out above 200mA if some circuits stay live for a while when the engine is off.

You shouldn't have more than a (very) few tens of milliamps current in its lowest, long-term off state, like undisturbed for hours. More than that and it's going to drain your battery. If you have a battery saver circuit then it could take upwards of an hour with no *activity* to reset the timer for it and get the true minimal current. I hope this makes sense, that it could start in a higher current drain state then after timing out, go down to the normal state which should be about 50mA or lower.

As far as the broken defrost element, access the connect to it. Put a low ohm resistor on it, say around 1 to 2 ohms. You "might" even be able to just short the two wires together for this test because you're not going to turn the defroster on, but I'd feel more comfortable using a resistor. Do not turn the defroster on! Because the defroster is not being turned on, the resistor does not need to handle high wattage.

This resistor would take the place of the defrost element resistance. Whether your alarm needs to be reset in some way, I don't know - consult the owner's manual. Once reset if needed, the resistor should fool it into thinking the heater element is still there. I'd also check the fuse if the defrost had been turned on and it was shorted in that state.

The other alternative is forget about it for now, just monitor battery voltage to make sure it's not draining too low, then see if replacing the window fixes the alarm problem.


You might get more vehicle specific help in a Trooper oriented forum. As far as transporting TVs, seems like you needed to use tie-down points, assuming it has some, and I would have put a blanket down and turned the TV on its face, so the tube is heavy-side down, or just driven a lot slower.

If you don't secure the load, even with a pickup truck you may damage the load instead of the vehicle... maybe even more with a pickup truck since the bed would allow it to slide around even more unless it has a rough rubbery bedliner.
 
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