HOLD light and seized brake caliper

[llitvack]

Hi all.
I've had an issue with a slowly flashing HOLD light, and was certain that it was a transmission problem.
After 20 miles of driving, when the engine got warm, the HOLD light would start to flash.

On taking my Bongo to the auto transmission specialist (who has some experience with Bongos), the fault was diagnosed as having nothing to do with the transmission at all. It was, rather, a seized brake caliper. Once the caliper was replaced, the HOLD light no longer flashed!

Has anyone ever encountered this problem? Also, can anyone explain how the HOLD light can be associated with a seized brake caliper?

Cheers.

[g8dhe]

Can't see it either, but do you have ABS ?

[llitvack]

Hi Geoff.
No: I don't have ABS. I have an early model 95 or 96 Bongo.
My problem is sorted ; but I'd be interested in what the connection is between brakes and HOLD light. I've not seen anything on this on the Forum before.

[Northern Bongolow]

thats a new one, but in theory its maybe possible, i had a bad fuel filter that did very similar, it pointed to a gearbox fault too, it took me days to track it to the filter.
so i suppose any problem/load that is out of the ordinary may flag in this manner.

[g8dhe]

I wonder if this was a report back at pickup, or if you saw the error code it returned ?

[llitvack]

Sorry: didn't check the error code. I left the mechanic the fact sheets from the Bongo members' area; but I don't know if he used them to diagnose the fault!

[Velocette]

Perhaps the sensors were detecting an abnormal load, rather like going up a steep hill but constantly?

[llitvack]

Well, eight months later, we think we have the problem licked.

After fitting a new brake caliper some time ago, we thought we had it fixed; but the HOLD still came on occasionally, with no reasonable explanation why. We were told by an auto transmission specialist that the problem was definitely not in the gearbox.

The garage (where the Bongo has been tucked up during the cold spell ) think it's a sticky solenoid. I presume it's the EGR vacuum solenoid (no. 2 in this diagram):

http://lushprojects.com/bongopartsmk2/c ... f02.html#6

A new one has been ordered. I wonder if this is an expensive part? Does anyone know?

Interestingly the cruise control (which is connected to the same vacuum pipe as the solenoid) stopped working when the HOLD light came on. Is this a clue that the two are related?

Ady told my missus last summer that I should get rid of the cruise control, because that might be contributing to the HOLD problem; but I hung on to it. Will I be vindicated? We shall see...

[Northern Bongolow]

13-995 in the lushy drawing is a one way valve, this valve opens when the suction on the air inlet side is greater than the vac, this presumes that the solenoid is open.

is your egr valve still in use, or still there but blanked off.
i just blanked mine off BUT left the solenoids in place and wired up, this enables the ecu to trigger them, this is important in my view as they are connected to the 2 cold start solenoids.
BUT MY BONGO IS MANUAL BOX.
the egr valve has a open/closed position sensor in it, so this could be your problem as it also talks to the ecu and may give you your flashing hold light.

the solenoids are about £60 new. but they are fitted on most mazda's of a similar age, both petrols and diesels with egr set ups on them. they are a mitsubishi part so are on those too. quite often they look or work differently, the vent may be on a diff port etc, simply pull the vent block off and swap over to a diff port to make it the same switch flow as the one you need. just put 12v to them to test them, and they are polarity concious, so check both ways to be sure.

shout me if you need, i have some lying around mate.

[Simon Jones]

The CC unit takes a feed from the speed sensor on the output shaft of the gearbox so there could be a connection between the two things. Try disconnecting the lead from the speedo to the CC unit and see if that makes a difference.