Using DMM in place of dealer tool
 

Hello All,
I'm trying to troubleshoot a problem with my backup lamps. I'm using the dealer manuals but am at a step to probe a a connector terminal. I'm looking to use either one of my DMM or test lights in place of the dealer to "J 39200 DMM". The step states:

"Use the J 39200 DMM in order to probe the connector terminal for CKT839 (PNK) to ground"

The succesful value is "B+" (By the way, the ignition will be in the run position during this test)

Though I have several electronic diagnositic tools, my electrical knowledge is pretty novice and I don't have a "J 39200 DMM". Can someone tell me how to use either a regular DMM or or a test light to perform this test? Once again, I'm pretty limited with electrical so telling me where to put the dial on the DMM and where to connect, what the value should be is not too much info.

I figure someone has probably asked this before, but I could not locate a thread that would help. Thanks much in advance!

Attach a link to your DMM, including a picture, so we know what you're working with. From there, it's pretty simple.

I have other ones if the one pictured won't work.

Use the 20V DC scale, (approx. 5:00 position on dial). Black probe in COM & red probe in lower right port. Connect black probe to a good clean body ground. Touch red probe to pink wire.


P19

I got 12.35. I assume that is equivalent to the B+ value on the dealer tool?

B+ is battery voltage. Your reading of 12.35VDC is fine. Was this reading at the neutral safety switch?

No, I took the reading at the backup lamp switch with ignition in 'run' and shifter in reverse (manual tranny)

Pink wire comes from the fuse, which means fuse is good, and the wiring to the switch is good. Next, test voltage on the grey wire at the switch: key in RUN position, shifter in reverse.

Just did next step in service manual...connect fuzed jumper wire between pink and grey, key run, shifter in reverse. Lamps lit. Manual says replace backup switch.

Got no reading off grey wire.