xr4x4rs

iTrader: (5)

got a wierd problem

when i turn my front heated screen on the batt light comes on, i can have everything on and not a problem and its only when the front screen is on the batt light comes on

would this be an alternator problem or a bad earth for the screen, ive checked everything and everything seems fine just carnt understand what it is and was wondering if anyone else has had this problem its on a sierra

jon@work

iTrader: (5)

The heated screen takes a feed from the blue wire that comes from the clocks and goes on to the alternator. I'd say it was an alternator issue, not a screen problem.

tabetha

Put a voltmeter on next time and see if the voltage is dropping sufficiently to show no charge, as jon says relay for front screen is energised one side by the live output from the alternator "ind"(dash warning light wire terminal).
I suspect a alt problem rather than wiring.
tabetha

xr4x4rs

iTrader: (5)

ok thats cool, i know the blue wire is a bit dodgy as sometimes i dont have a batt light, no drop in charge though when the screen is on

mark r

try your earth connection from the battery to chassis and the earth of the heater system

dojj

iTrader: (3)

the not screen loom is stand along and only connects to the ecu to raise the rpms when it's switched on

it also won't work unless the engine is running to save the drain on the battery

so simply get a meter across the terminals with the screen off, then switch it on and see what happens

xr4x4rs

iTrader: (5)

nothing happens dojj it stays almost the same 13.4volts from 13.7

dojj

iTrader: (3)

Hmmm, have you had thr dash apart to see if there is a fault with that? Sometimes it's the board on the back of the instrument cluster that causes this.

tabetha

Sort your charge lite first, find the relay for the heated screen take the cover off it and physically press together the contacts with the voltmeter connected, one side of relay coil is energised by the switch and the other by the alternator.
tabetha