Technical Bravo 1.9 JTD fuse box connectors

[barnacle]

Good evening Gentlemen,

Has anyone had occasion to strip the multiway connectors to the under-bonnet fuse box on this (or similar) cars? I have an intermittent (and exceedingly annoying) fault whereby the slow speed fan relay doesn't do its thing, causing the ECU to throw an engine error and for reasons known only to Fiat to drop the car into limp-home mode.

(This is particularly amusing when one has six hundred miles to drive down from the Isle of Skye in temperatures well below zero and with a fine selection of black ice and mountains to deal with...)

When originally observed, the fan relay would drop in and out with pressure on the fusebox; having stripped the fuse box (an interesting exercise I recommend to any passing masochist) I find it without obvious fault; conclusion is that the connection to the relay from the ECU is intermittent and this looks like the connector under the box. I'm hoping this is not a moulded part and that it can be inspected and perhaps repaired; I don't really fancy stripping and replacing the entire loom...

The relay checks out fine, though I'll drop a new one in on the off chance - but if anyone has any helpful hints regarding the connector, I'd love to hear them.

Thanks,

Neil

 

[barnacle]

Well, this gets better... The connector is easy to open: two clips hold the outer shell in place; easiest way to open is to poke a thin blade in both sides and just slide the insert out. You need to remove a tie wrap, also.

Bad news is that the connection looks fine.

The unit is now in permanent fail after a stage of intermittency. The fan2 relay clicks happily with an actuator test and if removed a sidelight bulb across the contacts lights cheerfully when actuated. Fan1 no longer clicks at all and is a permanent 12v; since a ground is supposed to be made to the relay this is presumably why nothing is happening...

However, that 12v indicates that there is a connection to the ECU and that the fault is perhaps internal to the ECU - not good. Ask me about a Fiat Coupe ECU and I can give you chapter and verse, but I know nothing about this one - any links to circuit diagrams, or repair services?

Neil

 

[barnacle]

p.s. eLearn has the most useless excuses for circuit diagrams it has ever been my displeasure to come across - it's all very well showing a very specific bit of circuitry but without some context it's not very helpful - for example, there's no explanation of the actuator testing system that I can find and no hint on the diagram as to where the testing is done. I am beginning to suspect that it is simply monitoring the signal level at the ECU output pin to see if it goes to ground or not...