Both my backup lights quit (my after market 130w halogens). While trying to fluke the relay I bumped the hot to ground for the relay switch.

I used the hot and neg from the reverse lights to trigger the relay to the b/u halogens. I have a hot coming from the battery and neg coming from the frame.

Now all my reverse lights are out.

The 20a fuse to b/u lights is good.

What am I missing? Is there another fuse that controls the reverse (oem) lights?

I have to fix the oem's before I can diagnose my aftermarkets.

Are you sure you didnt fry the bulbs when you bumped the hot and the ground? Maybe Im not understanding you right.....

IIRC, there are two fuse boxes, but I am unsuer if they both contain fuses for the backups. There is the box under the hood, and the one on the dash of the drivers side door.

Yeah.....

My dome light isnt working either....
Weird deal

I use the cargo lamp to turn mine on and it took me a while to figure out that the rear cargo lamp does not use the ground as a source. Maybe this is the same for your set up. If I remember correctly the dome light is the same as the rear cargo light.

I use the cargo lamp to turn mine on and it took me a while to figure out that the rear cargo lamp does not use the ground as a source. Maybe this is the same for your set up. If I remember correctly the dome light is the same as the rear cargo light.
if you're switching your relay from the cargo lamp and it doesn't use ground as source, how'd you make it work with the other lights that do use ground as source? did you just switch 89/89a on the relay wiring?

looks like lights feed from bcm, all bets are off, check all fuses?:o

Peekok do you have a larger version of that pic so I can print a nice copy?

CalDirt,
I tapped into the wires for the cargo lights and used plastic nuts (the same kind that are used for attachting a hood protector) and some garloc material to keep the metal brackets and screws from touching the bumper.
I am not using a relay for mine like others have done. I am using the fuse for the cargo lights. I feel this sould be enough safety since I don't leave them on for long periods of time anyways.

hey pc i actually had to shrink it to put it on the forum, i have know idea how to to it otherwise? i could send it to you by e-mail?:o

"Save the image as" whatever to your computer. Then use a program like IrfanView (available from www.tucows.com for free - small download) to resize it. Then print it.

Peekok

Can you post or email the ground distribution schematic that goes off the left bu light.

Also where is the b/u lamp switch?

mdickson"AT"email.com replace the "AT" with @

The backup switch is the NSBU. Neutral saftey backup. It is located on the side of the allison.

Peekok

Can you post or email the ground distribution schematic that goes off the left bu light.

Also where is the b/u lamp switch?

mdickson"AT"email.com replace the "AT" with @


And where is the bcm and what does it do?

Do you have the schematic for the bcm?

hey pc im gonna send you a bunch of schematics, get ready:p

The BCM is under the steering column, under the dash. It is the 'Body control module'. It controls alot of things like lights, door locks, etc.

hey pc im still looking for the ground schematics.

hey pc dont have that particular schematic but believe it is like all the rest of the "grounding". somewhere near the back lights they will just bring a pigtail out of the harness straight to frame.):h

hey pc just thinking is there anyway you could have "accidently" pinched/ cut lighting wires when you installed supertank? just a thought.:rolleyes:

"hey pc just thinking is there anyway you could have "accidently" pinched/ cut lighting wires when you installed supertank? just a thought."

No.......

They (all 4 oem + 130w bu lights) were working until I got into yellowstone. Then I lost my right light. It faded and then went black. Then the left light (after market) went out.

Both oem's were working the whole time.

I was using my multimeter on the relay when I grounded the + wire. The lights (all 4) have not worked since.

I must have melted a relay or bcm somewhere.

I'm thinking you smoked the bcm. Should be pretty easy to diagnose with that wiring diagram. Worst case scenerio you should be able to go around the BCM altogether and wire in a relay.

hey pc as you can tell from the wiring diagram that both oem backup lights are parrallel fed from the bcm. there is no overcurrent protection from the bcm to the lights, that is not to say there is not protection inside the bcm. i have know idea what load rating the signal output of the bcm is for the backup light circuit, maybee someone else does. i take it you have tied your aux light relay into the circuit between the bcm and the light bulbs, therefore when park/nuet/posit. switch is made with ign. switch at run , bcm should output 12 v + and energize relay. ok now, if you "grounded" the signal output from the bcm theres a possibility you burnt that output. normally there is supposed to bo a resistance there(b/u lightbulbs). you would of had to ground it with ignition on and shifter in reverse. its just a theory not knowing the internal makeup of the bcm.

Whats a bcm cost?

so tell us what you found? :confused:

I have no idea what a bcm would cost. Probably several hundred dollars.

Whats a bcm cost?
<TABLE cellSpacing=0 cellPadding=3 width=567 border=0><TBODY><TR background="images/trans.gif"><TD class=reg vAlign=bottom>GM PART # 15198116
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PACK QTY: 1</TD><TD class=reg vAlign=bottom>CORE CHARGE: $0.00
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OUR PRICE: $152.25</TD><TD align=right><!--QUANTITY:--><!--<input name="p15198116" type="text" value="1" size="2" maxlength="3">
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Youve probly figured this all out by now, but I did the same thing a couple years ogo on the 03 dually. Turned out the dealer only had to reflash the BCM. Got lucky!!

problemchild,

Fix your BU Lights yet?
The schematic peekok posted looks different than my Helms manual for the 2002.
With the 2002, the 12VDC originates at Fuse Block -Underhood with B/U LP Fuse 25A, Hot in Run and Start. Then it travils through contacts of NSBU switch. Then power travils through a second fuse, VEH B/U Fuse 15A, also located in Fuse Block -Underhood. This second fuse also powers Inside Rearview Mirror.
Both BU lights are grounded at G401.
My schematic shows no interaction with the BCM.

Helms 2002, page 8-315.

havent brought it in yet.