Diagnostics ?

KAM · Postby **KAM** » Thu Dec 13, 2007 11:29 am

How do I read the diagnostics for a 2001 NB8B ? :?:

I have a copy of the US 2002 Workshop Manual which sais its OBDII and needs a reader (WDS ?) but I seem to remember someone on here stating we didn't get OBDII until 2003

Found the Diagnostic connecter in the engine bay on the passenger side but there is no indication of which pin is which. The Electrical Diagrams in the Workshop Manual show a DLC2 (Data Link Connector) which has \"GND\" and \"10\" pins which looks the same shape as the Diagnostic Connector. Can I connect GND and 10 to get the codes from the light flashing on the dash :?:

The Worshop Manual also shows 2 Oxygen Sensors (Front and Rear) is this for US only :?:

AUS only has 1 Oxygen Sensor, Correct :?:

Kym

Garry · Postby **Garry** » Thu Dec 13, 2007 11:39 am

What flashing light on the dash? I didn't think AUS NA/NB's had an engine check light?

The NB8B diagnostic box in the engine bay has the same pin locations as the NA's. So if you find an NA pinout fo the diagnostics box then that will give yo the information you need.

You are correct, OBDII only came to the MX5 in the NB8C.

Aus cars only have 1 oxygen sensor, (pre cat)

KAM · Postby **KAM** » Thu Dec 13, 2007 2:56 pm

Garry wrote:What flashing light on the dash? I didn't think AUS NA/NB's had an engine check light?

Thanks Garry

I had read about the flashing light on the miata.net site.
How do I get the codes from my car :?:

if there is no engine check light :?:

Kym

Garry · Postby **Garry** » Thu Dec 13, 2007 3:09 pm

You make up your own light using an LED and a resistor and connect it to the correct pins in the diagnostics box. It's all set up for the Mazda techs and Mazda's diagnostic machine. They dont want backyard mechanics playing with their creations.

There are instructions around the net somewhere on how to build the light and where to connect it in the diagnostic box. I think Caffeinne may have written something up about it on here at some stage so try doing a search here or on miatanet.

I did it a long time ago but I cant remember the specifics of what I did.

adamjp · Postby **adamjp** » Thu Dec 13, 2007 3:55 pm

MX5 Club of New Zealand have the how to on their site.

http://www.mx5club.co.nz/maintenance/engine_diagnostics/

KAM · Postby **KAM** » Thu Dec 13, 2007 4:13 pm

Thanks Adam

Couldn't find that info searching this forum.

Kym

KAM · Postby **KAM** » Thu Dec 13, 2007 8:50 pm

The LED needs to be connected between B+ and FEN
I cannot find a diagram anywhere which shows a FEN pin.
All the diagrams show
SGND
KLN
TEN
B+
FSC
FAB
IG-
GND
F/P
TAB

Anyone able to tell me which pin is FEN :?:

JBT · Postby **JBT** » Thu Dec 13, 2007 9:24 pm

Could it be a typo? TEN = FEN?

KAM · Postby **KAM** » Thu Dec 13, 2007 10:20 pm

JBT wrote:Could it be a typo? TEN = FEN?

I don't think so as it states to connect TEN to one of the GND's
and the LED between B+ and FEN
B+ is Battery so the LED between Battery and Ground will light it permanently.

KAM · Postby **KAM** » Thu Dec 20, 2007 4:48 pm

This is the layout of the diagnostic conector according to the US Workshop Manual

--------------- -----------------
| | KLN | | TEN | B+ |
| | | | | |
-----------------------------------------------------
|SGND| | | | | FSC | |
| | | | | | | |
-----------------------------------------------------
| | TBS| | | | |
| | | | | | |
----------------------------------------------

----------------------------------------------
| FAB | IG- | GND| | F/P | TAB |
| | | | | | |
---------------------------------------------
| | | | | |
| | / \\ | |
-------------- --------------

No sign af a FEN terminal.

According to the wiring diagram
KLN connects to the PCM (ECU) and ABS if fitted.
TEN connects to the PCM
B+ connects to Battery via the Ignition switch
SGND connects to the DLC2 (Data Link Connecter under the dash ?
FSC connects to the Cruise Control Module
TBS connects to the ABS
FAB connects to the SAS Control Module (Air Bag)
IG- connects to the PCM
GND connets to Ground
F/P connects to Fuel Pump Relay
TAB connects to the SAS Control Module (Air Bag)

As it states to connect TEN to Ground that only leaves KLN and IG- which are connected to the ECU to give any output.
I've connected a Multi meter to these points and cannot see any changing output. IG- to B+ gives a perm 12V (KLN to B+ = no voltage).

Cannot find an AUS diagram for the Diagnostic Connector anywhere.
The US and NZ instructions all state the layout is printed on the inside of the Diagnostic Lid but this is not the case on my 2001.

Anyone have this info printed in the lid ?
or
A copy of the AUS Wiring Diagram for a 2001 NB8B ?

KAM · Postby **KAM** » Thu Dec 20, 2007 4:52 pm

Took ages to draw that with spaces and dashes and then it all got corrupted when I submitted the post.

Will scan the wiring diagram when I get home tonight.

Caffeine · Postby **Caffeine** » Sat Dec 22, 2007 10:01 am

Found it!

Be careful as B+ is a direct feed from the battery, it'll put 30 amps through anything you short it with, i.e. wedding rings etc! (gets hot real quick!)

I've used the LED method on my car, somewhere there's a list of what code equals what, but my car just gave the single ignition pulse, meaning nothing is wrong