SurWagon

RED/BLUE pcm lq4 into a Grand Wagoneer.

Blue pin 58 to OBD2 pin 2 showing ~0.4v fluctuating

OBD2 4 & 5 grounded

OBD2 16 is hot at all times (run through silverado fusebox)

Engine starts up and appears to run fine. However, when I hook my ELM 327 up it says failure to detect protocol. I'm confused why it doesn't work.

Any ideas?
-Nick

bczee

iTrader: (12)

Nick

Is that ELM 327 a Bluetooth device ?... I heard that some of the eBay ones may or may not work all of the time.

Might try a cabled Scanner to verify if you are getting Serial data or not.

BC

SurWagon

It's a serial cable with a USB adapter. I've used it on a subie and a ford ranger with no problems

SurWagon

I've also wired up an 02 silverado dash and that does not seem to function either. The idle is high (i'm guessing around 2k).

The pcm was tuned by wait4meperformance. I told them to remove VATS. Could that have caused the serial data issues? I saw in another thread that the serial data voltage should varry between 0-7v. I'm getting 0.05-0.4ish.

LS1MCSS

iTrader: (18)

Here is a copy/paste from from another page I found. It looks like 0-7 volts is correct,

"The class 2 data was
at a resting level of 0 volts and was pulled high to around 7 volts to talk."

SurWagon

Ran a new wire from pin 58...nada
Tried pin 59...nada
cleaned connectors ....nada

Still getting 0.2-0.4v.

Any ideas, has this happened to anyone else?

LS1MCSS

iTrader: (18)

Can you get a different scanner from someone and try it? I think the problem is with your scanner.

SurWagon

Went to AutoZone and got the cheapest scanner and it was able to read the computer. No error codes.

I guess my scanner doesn't like the pcm.

Thinking of ordering a PLX Kiwi bluetooth for the droid. My dad has one and likes it. However, I would like hptuners so I can play with things.

SurWagon

So, I have to use pin 59 for the OBD2 port to work. Tried putting it back in 58 and running 59 to the dash cluster....fail.

Just a heads up to future swappers

aknovaman

iTrader: (7)

Bluetooth, just eBay elm327. Cheap and functional.

bczee

iTrader: (12)

I had picked up one of them ebay elm327 last month, using it with my Xoom and installed Torque... works pretty good. Still learning about is other Advanced functions. Fun to play with and monitoring while I driving down the road.

BC