Ob2 port won't read codes, personal reader and store reader - 99 s70 na Topic is solved

[smacknab]

I noticed recently that my obd2 wasn't scanning codes on my $20 dollar reader, but I figured my scanner was broken.

Today a Check Engine Light came up while driving and I pulled into an Advance to have them read the code and they said they weren't getting anything from the obd2 port. We tried a couple times and nothing was working so I figured nothing I can do right now.

Funny enough, when I started the car to drive home, the CEL was no longer on. So im not too sure how much I should worry about it.

Looking on the rest of the forums, I haven't seen anyone 'solve' this problem, other than suggestions to blow dust out of the obd2 port or check fuses. I also read that on a 97 s70, the obd2 is on the same fuse as the interior lights, but my lights are working. I suppose I'll check the fuses and blow some dust tomorrow, but if anyone else has a tip I'll look into that too!

Thanks!

[Matty Moo]

From what I remember the cig lighter fuse powers the obd port.

[RickHaleParker]

Look for power on pin #16.
Pin #16 Fuses: 11C/5 & 11A/6.

[smacknab]

Look for power on pin #16.
Pin #16 Fuses: 11C/5 & 11A/6.

Checked my cig lighter fuse and it's good. Powered from rear cig lighter, front has never hade power (It looks pretty clogged with junk).

Checked for power from 4/5 to 16 and nothing. Only seemed to find power there with a couple other ones. Maybe there's a ground I forgot to hook back up?

Also the cel came back on, and now has turned off again..

[RickHaleParker]

Fuses 11A/X are the large fuses under the hood.
Fuses 11B/X are the small fuses under the hood.
Fuses 11C/X are on the CEM under the driver's side of the dash.

[smacknab]

Fuses 11A/X are the large fuses under the hood.
Fuses 11B/X are the small fuses under the hood.
Fuses 11C/X are on the CEM under the driver's side of the dash.

Ah ok I'll take a look for those!

[wizechatmgr]

Probably won't be the large ones. Others should blow first (in theory)

[jimmy57]

The Immobilizer module is in the obdII line to ECM, they use the wire for diag and for immo communication. I don't have a wiring diagram handy but you unplug immo box and jumper the pin in from diag port and the one out to ECM and then try diagnostics with ECM.

[abscate]

Check the voltage from 16 to a chassis ground to see if pin 16 has battery voltage

[misha]

The Immobilizer module is in the obdII line to ECM, they use the wire for diag and for immo communication. I don't have a wiring diagram handy but you unplug immo box and jumper the pin in from diag port and the one out to ECM and then try diagnostics with ECM.

That's correct for '96-'98 cars,jimmy57,which use K-line for communiction.

But '99 use CAN protocol,so that may be different on these '99 & '00 cars since modules are "married" to the car....at least on EU market cars.
I don't know if this still apply for U.S market cars.