[hampt135]

Hi, need help with problem I assumed was becm related, symptoms window switch pack , hvca , sat nav, radio wipers and cigar lighter all not working,becm has been back and forth between repairer who assures me its working, it was tried on three different vehicles.Sent fuse box back as well last time that also passed testing. Hawkeye tells me the mentioned packs aren't communicating on my vehicle . Tried simple test to cigar lighter, showing continuity on feed wire back to becm and earth, took top off becm seems relay 7 feels like it is switching but no output from becm.

All packs work through Hawkeye. If anyone's got any ideas or could point us in right direction would be really appreciated. It's a 01 plate 2.5 diesel

 

[Bolt]

What does "All packs work with Hawkeye" mean?
If you say that nothing is communicating with the vehicle, I will assume that means the BECM, thus Hawkeye should not be able to command them through the BECM? If HE can move windows etc, then BECM good. Possibly trust and believe whoever tested it and move on?

So, if the BECM is known good, and fuse box is known good, that leaves Earth Points, wires, and connectors. Get RAVE and trace the connections. Behind L and R kick panels is a beaut place for corroded plugs...... Start with Earth points. happy hunting!

 

[RRToadHall]

Why are you insistent that it is a BeCM issue? Have you checked your maxi fuses? have you checked your wiring harnesses and connectors for corrosion?

 

[hampt135]

I wrongly assumed that it was a becm fault and sent it away to be checked.
All maxi fuses are ok, I've tested for 12v on each of the large feed wires on becm and the main ground all ok. Power going through all becm fuses also. Ive checked grounding points under seat, drivers side kicker panel and under wiper cowl, all look ok, can you point me towards other grounding points?. The hawkeye can operate the windows and wipers fine which I find a bit strange?! Does Hawkeye command through becm?

Thanks

 

[hampt135]

Hi ,also is there a specific ground post for Windows ,wipers scratching head on how Hawkeye can operate windows wipers, sorry about posting as becm problems it was just my initial thought, if I posted symptoms I'd expect it to come back as becm, sorry first time I've ever posted on a forum,(being a bit of a dinosaur), just don't know where else to turn

 

[RRToadHall]

Rave has full wiring diagrams and photos of each connector and ground. I still think it is a corroded harness connector.

 

[Bolt]

Hi ,also is there a specific ground post for Windows ,wipers scratching head on how Hawkeye can operate windows wipers, sorry about posting as becm problems it was just my initial thought, if I posted symptoms I'd expect it to come back as becm, sorry first time I've ever posted on a forum,(being a bit of a dinosaur), just don't know where else to turn

I believe the Earth point in common to all you have mentioned is under the HVAC in the center console, so ya gotta open up the sides and have a look. There are also some splices in the earth wires leading from there. Could be broken wire, but more like the main point. As for Hawkeye being able to control things? Yes, it commands the Becm to activate things, not the actual items themselves directly. bad earths on a P-38 will cause the most unlikely and random things to occur! Check all for clean and tight. Look in Rave as TH says.

 

[hampt135]

Thank you for taking the time to reply, delve into dash for earth point for starters,(apart from earth under wipers they've all been pristine up to now, even one under fuse box ) then it looks like it could be needle in a haystack time, thanks again

 

[95classiclwb]

could be failing fuse box in engine compartment.

 

[Gordo51]

Thank you for taking the time to reply, delve into dash for earth point for starters,(apart from earth under wipers they've all been pristine up to now, even one under fuse box ) then it looks like it could be needle in a haystack time, thanks again

I was having trouble with the windows, sunroof and mirrors sometimes not working. There is ground point with 3 wires behind the passenger side kick panel. This looked clean and shiny but I took the nut off, cleaned all the connections with solvent and put it back together tight. So far everything has worked consistently. You can't judge the reliability of a connection by just looking at it. Suggest removing and cleaning, or at least loosening and wiggling before re-tightening.

 

[marty_nz]

It could also be a problem with the wiring from the ignition switch through the loom to the BECM... I've had it before with another owner who was adamant his BECM was faulty - to the point where I reprogrammed a spare one FOC and sent it to him as I was sure it wasn't the fault.

A couple of weeks later he came back to me and said that there was a break in one of the wires from the ignition switch to BECM (in the loom in the drivers door sill under the trim) that was causing the BECM to not receive the signal from the ignition switch, and thus not powering up a load of things.

I'd check the continuity on those wires too, to be sure.

 

[hampt135]

Thank you for all your posts, especially the last one that pointed me in the right direction, if anyone comes across this problem, it was one of the wires that comes out of ignition, in my case pink and white, entered becm under becm fusebox, no visible signs of break but found continuity testing. Inner cable broken about 4 inches from becm can only assume must have been stretched by getting in and out of vehicle .For the technically minded it was ignition switch position 1 cable, thanks again

 

[RRToadHall]

That's a killer follow up. Testing continuity can be a royal pain on any circuit. Congrads.

 

[ColoradoCrow]

Awesome. Great follow up. I’m bookmarking this one for sure.
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