Flashing Hold Light, Only Changing Up on Very High Revs

[snowrat]

Hi All
I have a 2.5td 2WD and have the current problem, hoping someone can help with ideas of what to check.
Slovakia so no Bongo friendly garages here.

About a week before had a perforated drivers side radiator hose and gearbox/engine got soaked.

The driving on motorway got loss of power and hold light started flashing.

On inspection found SS exhaust had come away in engine bay and flange connection was sitting about 5 inches apart. Some wires could have been burnt and have been replaced by garage. Exhaust has been reconnected.
After this work hold light is again flashing after about 3 or 4 miles of not doing.
Now gearbox only changes up after 3000 to 4500 revs, not the normal 1500 to 2000 revs.
Sometimes when we were doing a test run if you kept speed (under 20mph) and revs low for ages it did change up earlier but still at many more revs than normal

I am thinking it must be a sensor/control issue but at a loss just what to ask the garage to try first.
They have diagnostics equipment but not the connector for the Bongo.

Getting pretty desperate as I'm Slovakia and need my Bongo healthy So any ideas/help appreciated.

[Northern Bongolow]

it looks from the pic that you have the old shape bongo is this correct.

i know its daft but is the hold button pressed on.

flashing hold light usually means an electrical supply /charge fault have you tested the output of the alternator, the gearbox is very sensitive to voltage drop/change. alternator could have been cooked with hot exhaust gasses under the seat as it needs cool air to cool the diodes.

what wires were damaged as most of the controlling stuff is on the other side of the engine. if it is a sensor wire that has been damaged these sensors mostly work on resistance readings that change with temperature/speed etc, this resistance can be altered by bad connections/repairs so maybe the first check would be check again on any new connections/repairs made, then during repairs has a plug been pulled, again bad connection.

[jimmo62]

can you get anything out of the diagnostic connector - for older models the instructions are here -

http://www.philmcfadden.co.uk/MazdaDiagnosticBox.htm

I think flashing hold light is the way the ECU signals there is an error code to read.

[Northern Bongolow]

try this link and the link within it.
rev counter/sensor on front of engine etc.

http://www.igmaynard.co.uk/bongo/forum/ ... of#p648974

[snowrat]

Thanks everyone, very useful info, will pass onto garage and hope they are successful.

The wires that were shortened after some being burnt ere under the passenger seat adjacent to a large pipe covered in foil and above the exhaust flange connection. Does one of these carry the signal from the rev counter sensor and if so, does anyone know what colour it is?

[Northern Bongolow]

i will have a look at mine tomorrow for the wires you refer to, but the sensor for the speed signal is on the front of the engine on the driverside so it would seem to be unlikely. the sensor is at the front driverside corner just under the front of the fuel pump, this is held in with a ten mm spanner sized bolt, if you undo the bolt and gently pull on the sensor, its held in with an O ring, you may find a thimble full dollop of oil, clean the hole and the sensor face with a cloth and see if this is any better.

will let you know what i find re the wires tomorrow.

heres a pic of where the sensor is located.

http://www.igmaynard.co.uk/bongo/forum/ ... 49#p672854

have you seen these pages before, they show most bongo bits, click on the year then the diesel then the wiring etc. it shows where the sensors are located, once you have had a bit of time to work things out they are really handy.

http://lushprojects.com/bongopartsmk2/

67-sh1 no1 and no2 on this link goes to the gearbox. if you click on the number on the drawing quoted it highlights on the left as auto gearbox wire link. look closely on the middle drawing on the right you will need to work out which way is up,(look for the gear selector and peddles)

http://lushprojects.com/bongopartsmk2/c ... o=.html#19

[snowrat]

Thanks again.
Not sure if it is one of those 2 parts but the mechanic has found a part that seems to be disconnected. he told me on the phone that it has a resistor symbol on it.
He's going to see if he can open it and reconnect it. Just waiting to hear back.
I'll see if he can identify it for me.

[Northern Bongolow]

18-831 on this drawing mate.

http://lushprojects.com/bongopartsmk2/c ... o=.html#10

[snowrat]

18-831 on this drawing mate.

http://lushprojects.com/bongopartsmk2/c ... o=.html#10

Would that be this, which is what the garage has sent me a link to...
http://www.ebay.com/itm/Standard-Motor- ... 8w&vxp=mtr

Other than the US options on eBay, does anyone know where I could source this?
Would a 2nd hand one from a breaker be suitable?

[Northern Bongolow]

no thats a speed sensor, the resistor is mounted on the nearside chassis rail under the passy seat opposite the turbo and exhaust flange. if you look at the last link i put up you will see the arrow on the drawing pointing to its position on the bongo.

that speed sensor is different to the one on a bongo so i suspect it is the wrong one anyway, the speed sensor is mounted on the front driverside corner of the engine so is unlikely to have been involved.

[snowrat]

Thanks again. The garage told me it was that part, but they may have got it wrong.

Do you have a part number or photo of 18-831 ?

[Northern Bongolow]

if you go on to the drawing, find the number 18-831 click on the number on the diagram till its highlighted then look in the left margin on the drawing it opens up to reveal what i presume is the mazda part number.

if it were me i would photo the part on the drawing with my phone and send an email or picture text to these guys
http://www.bongospares.co.uk/.
he will post you a second hand one with the wiring loom .

[rita]

[Alacrity]

Unless I am going blind I can't see anyone has got the fault code(s) yet? There is no point in speculating as to what the issue is, you MUST read the fault codes then you will know which area to look in, either speed sensor/wiring or TPS/wiring I would guess. There are 16/17 different reasons why the hold light will flash according to the chatrt Jimmo62 has posted up earlier in this thread on how to retrieve the code(s). I have a listing that list an extra code to Jimmo62's listing: 16 - EGR valve.

[mikeonb4c]

Unless I am going blind I can't see anyone has got the fault code(s) yet? There is no point in speculating as to what the issue is, you MUST read the fault codes then you will know which area to look in, either speed sensor/wiring or TPS/wiring I would guess. There are 16/17 different reasons why the hold light will flash according to the chatrt Jimmo62 has posted up earlier in this thread on how to retrieve the code(s). I have a listing that list an extra code to Jimmo62's listing: 16 - EGR valve.

I'd do exactly as he says, Alacrity knows his stuff 100%