I decided to fix all the electrical issues of my car 1995 Accord EXI and started from rear window defogger. when i saw the circuit diagram it was piece of cake but when i jumped to real world i was in trouble.

i didn't take ground lines seriously and rechecked circuit diagram. when comes to ground issue there are points like G901, G402 and each individual has different grounding point. oh, i forgot to mention, my defogger doesnt work and the resistance on ground line is 200Ohm. in the diagram i saw the grounding point is G901

if i have to connect every single bit from battery negative then it will be a new wire harness.

Would you please explain where to find the ground point of G901 or what it explains by this number.

PS: i have seen other CD and some more grounding points like G401 G402 G451 .... Pulling my hair

 

First thing I would like to know is does the defogger indicator light on the dash come on or not regardless of the fact that the rear window does not defog?

 

G801 (rear fogger ground) is under the rear window deck cover on pax side (LH Drive) or on driver's side for RHD.

A resistance on the ground side of 2000 ohms is suspicious. Usually you will get either open or ground. A corroded connection might have this amount of resistance. Was the ground lead unplugged from window defogger connection? If not, then resistance may be incorrect.

good luck

 

Do you have a manual? It has drawings of where the ground points are located. Look on the Common DIY and Info. Threads page if you need one. Consider copying/pasting the Ω symbol; zeros and "O"s are tough to distinguish between.

 

Thanks guys for your input

Yes, defogger light on the dash switch does comes on

Defogger battery and ground voltage connectors looked good, although i sprayed electrical contact cleaner. the resistance is 200Ω on the ground terminal connection.

i found battery voltage o opposite side and voltage decreases along with the rails towards ground terminal. one bottom rail is open but that shouldn't bring down the whole defogger system.

 

one interesting info
my car is RHD
one day suddenly the power window of the rear passenger (just behind the front passenger side) side stopped working. may i suspect the same ground issue?

 

Window issue likely unrelated to rear window defogger. Typical problems are stuck regulator movement, dirty switch (try seat position switch), fuse, faulty drive motor, and wiring/connector defect.

For voltage to decrease along length of RWD, current flow must be present. How do you know the defogger is not working? All you can do is supply voltage and ground. If it still won't work, the window resistance strips may be at fault.

good luck

 

I have checked ground to RWD and its ok. among several lines only bootom line has open (i have checked resistance on these lines). i did not measure voltages along the lines but checked resistance and its decreasing near ground. still when fogged it doesn't clear it.

Expecting a kind guideline.

 

So you have ground and good strips, then voltage is missing presumably. Have you confirmed missing 12V on opposite side from ground?

good luck

 

its not exactly battery voltage, a bit drop and nearly 11V is there? this is enough voltage i think.