Diagnostic Connector

[BennyD]

Am trying to us the diagnostic functions on the ECU to find out why my glowplug light is flashing, as described by Phil McFadden:
http://www.philmcfadden.co.uk/MazdaDiagnosticBox.htm

The problem I'm having is that although my connector appears to have the same pinout as the one on his page, the pins labelled as being needed (TEN, FEN, G, B+) don't all seem to exist. There also seems to be at least one other pin configuration that I've found:
http://igmaynard.co.uk/bongo/forum/view ... b2#p621719

Any ideas?

[dave_aber]

I went to look at an N plate van last week, and I found the same - many pins missing, impossible to read the code in the "short and voltmeter/bulb" method.

In that case, what transpired was that a helpful relative had removed Fuse 1 to prevent the badly-wired stereo from draining the battery. Once I'd disconnected the stereo, and refitted Fuse 1 (and blown Fuse 9 trying to get the diagnostic to work, and then replaced F9) then the flashing stopped.

I did read that it's not uncommon for the diag connector to be missing a few pins. I've not seen any suitable follow-up though which details how you are supposed to read the codes....

[jimmo62]

If you look at the codes for the TEN codes you will see they are only for engine types FE and KL (i.e. not WL-T which is the Diesel engine which you have) - since you have the Diesel Auto you need to look at the Auto Gearbox codes

[BennyD]

Well spotted! Although I've managed to interrogate the AT successfully in the past, but that doesn't tell you anything about the engine management. Surely there is some overlap between WL, FE & KL (eg temp)?

Also interesting to note that my stereo also has no permanent live feed, although I definitely do have a full complement of fuses. Some further investigation needed I guess...

[GreenBongo]

There isn't any engine management as such, the only controls are in the AT ECU.

[BennyD]

I see - so the ECU controls everything including AT? Had a look inside the connector and there definitely aren't the wires for FEN & TEN, so isn't just a case of missing pins.

If it's the case that there is only one system to interrogate, do you know why both my glowplug light & hold light can both flash? Currently only glowplug light is flashing (but hold light ha flashed in the past)

[Simon Jones]

Have you read the codes as per the factsheets? If so, what are the results?
Glow plug: http://www.igmaynard.co.uk/bongo/member ... ostics.pdf
Hold light: http://www.igmaynard.co.uk/bongo/member ... dlight.pdf

You mention you don't have pins for FEN and TEN. It may see like a silly question, but are you looking at the connector the right way round? It's upside down compared to some of the diagrams.

[BennyD]

Definitely no FEN or TEN pins or wires present.

Just tried using FAT & TAT and got 38 (3 long then 8 short flashes), which I've looked up on www.iequus.com/Dtc as P0038. It came back as:
'HO2S Heater Control Circuit High (Bank 1, Sensor 2)'

Any thoughts on what this could mean? Only glow plug light is flashing currently.

[GreenBongo]

That look up is for OBD2 codes only, you need to find the codes for the Bongo, I'm surprised that they aren't in the fact sheet. You certainly don't have any O2 sensors.

[BennyD]

There is a code 38 in the fact sheet, but doesn't give a definition and says to look it up as P0038 as far as I can see?

[GreenBongo]

The petrol engines seem to use the same codes as OBD2 but the diesels are different. I've just dug out my FSM it states code 38 = 'scavenger back up power supply circuit system'. It states to check the connection between ECU pin 2B and the battery.

[BennyD]

Amazing thanks - will check that out shortly!

[jimmo62]

The service manual says Code 38 means Fan for driving back up power supply circuit system (for manual vehicles).
Detail - the main relay does not operate when the engine switch is ON

Debug - check the main relay and the EcU connector

Not sure which relay they are on about but should be possible to work out from the wiring diagrams - it looks like the relay is driven from terminal 2H on the ECU so you should be able to trace it thru?

For automatic vehicles it means Fan for driving back up power supply circuit systems
Detail - the fan does not operate when the engine switch is ON
Debug - check the ECU terminal 2B is live, if it is not you need to check the fuse and connectors/wiring