P38 Gremlin

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It's worked. Everything in this range works aside from the buttons on the steering wheel. Stereo is because the aftermarket head doesn't support it and the cruise is probably a rotted pipe like he said. But the thing that makes me believe it's all related is I turn the wipers on so I know when everything turns on. When the wipers stutter and work, it's a sign the stereo and HVAC follow. Everything else works. And this just started. The ride level works, And the stereo is getting power despite not turning on, because I can eject the disc in the tray and pop another in. It and the wipers and hvac just won't turn on. Like I said before, they finally literally stutter and turn on after maybe 15 minutes of driving. Could it be the battery? By the way. While everything is stuttering the BECM is clicking under me, I'm assuming because everything is powering on and off...
 
I read that if the alternator isn't pumping out enough juice that the wipers and HVAC would flicker, but I pulled a reading and my battery sits at 12.6-8 and after starting it, it goes back up to 14.5-7. As corroded as the exterior of the BECM was, everything else works, that is the frusterating thing.
 
Do you get power on both of the feeds to the stereo/HEVAC? they have a permanent power feed, and then they also have a switched (ignition) power feed that wakes them up...

From memory, on the stereo, the purple wire is the permanent feed and the White/Pink (bigger thick wire) is the switched 12V

If you get power on BOTH of those when you should, then to me it points to a bad ground somewhere.

If you don't have switched power to the radio/HEVAC, then it could be an issue on the BECM power board - but it could also be on the wire from the ignition Pos I switch to the BECM to tell it to turn those functions on (I could be wrong on that - I'm away working at the moment (in the USA co-incidentally... New Jersey at the moment), so can't just 'pop out' to remind myself, and my head is buried in technical stuff for work rather that RR wiring!)

I'd check both power feeds first - and then report back, as that will help point to where the fault lies... whether it's on the power side, ground side, or the input switching side.
 
So as far as I remember from earlier, they are getting power. The backlight of the HEVAC comes on, and the stereo will eject discs. It just doesn't know when to turn on I believe. After driving for a while it will literally stutter on, and you can hear the BECM clicking as it turns on and off over and over until it stays on. The wipers also do not work when this is going on. Dunno if this helps. I think it may the POS1. I have literally torn my carpet up and cleaned everything per mozz and still no joy. Verified with my multimeter that the constant power to the stereo and HEVAC is 12.3 ish.
 
If you are getting a crazy chatter of relays clicking, then it does sound like it might be POS I input to the BECM that is causing the issue.

The next step would be to check the continuity of the White/Pink wire (it's a thin one - not a thick one that carries 12V power) from the ignition switch (it plugs in somewhere under the steering column from memory) and ends up on pin 13 of the 16 way white connector on the BECM, which is under the fuse box. That wire should have a constant connection to ground when the ignition is in POS I or II.

If it's not there or intermittent then the issue is in that wire - I've had it before from a guy in the UK where the problem was an intermittent break in that wire in the loom where is runs in the sill (same area as you show in your pictures).

I'd add that to the list of things to check tomorrow... If you're unsure about it, then if you poke a wire into the back of the connector so it makes contact with the pin (with the connector plugged in) and ground that, it will mimic the ignition being in position 1. If you then turn the key to position 2 and it all works as it should, then you've proven the problem is on that wire somewhere. If it still doesn't work when you mimic position 1, then it points to it being internal in the BECM.

If I were a betting man, I'd say that the pos 1 wire has an intermittent break in it, causing your problem.
 
martyuk said:
If you are getting a crazy chatter of relays clicking, then it does sound like it might be POS I input to the BECM that is causing the issue.

The next step would be to check the continuity of the White/Pink wire (it's a thin one - not a thick one that carries 12V power) from the ignition switch (it plugs in somewhere under the steering column from memory) and ends up on pin 13 of the 16 way white connector on the BECM, which is under the fuse box. That wire should have a constant connection to ground when the ignition is in POS I or II.

If it's not there or intermittent then the issue is in that wire - I've had it before from a guy in the UK where the problem was an intermittent break in that wire in the loom where is runs in the sill (same area as you show in your pictures).

I'd add that to the list of things to check tomorrow... If you're unsure about it, then if you poke a wire into the back of the connector so it makes contact with the pin (with the connector plugged in) and ground that, it will mimic the ignition being in position 1. If you then turn the key to position 2 and it all works as it should, then you've proven the problem is on that wire somewhere. If it still doesn't work when you mimic position 1, then it points to it being internal in the BECM.

If I were a betting man, I'd say that the pos 1 wire has an intermittent break in it, causing your problem.
Click to expand...
Looking at the photos of the becm someone has already put an extra wire (the red one) to bypass something. What does that wire connect to? Check both ends of it and post what colour wire it is attached to.And you have a 2pence piece under the cable clamp in photo 2. My Dad always said the Yanks were overpaid.:D What he actually said,when he was running the gauntlet on the Russian convoys was, they are over paid,over sexed and over here.:D:D
 
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tomcat59alan said:
Looking at the photos of the becm someone has already put an extra wire (the red one) to bypass something. What does that wire connect to? Check both ends of it and post what colour wire it is attached to.And you have a 2pence piece under the cable clamp in photo 2. My Dad always said the Yanks were overpaid.:D What he actually said,when he was running the gauntlet on the Russian convoys was, they are over paid,over sexed and over here.:D:D
Click to expand...
The red wire is my fuel door release switch. Connections are good. I found the old ones but they aren't attached to anything. They are green and black.
 
OBX97 said:
Here is a video of what is going on, finally managed to grab one.
Click to expand...

Wiring fault is where my money is at.

Congrats on the assimilation and driving on the correct side of the road...
Just another couple of hundred million in the colonies to get educated :p
 
ukadamwest said:
Wiring fault is where my money is at.

Congrats on the assimilation and driving on the correct side of the road...
Just another couple of hundred million in the colonies to get educated :p
Click to expand...
Haha nah right side of the road is the right side. And I still have to check that ignition wire. How do I get to it? Another thing, I'm going to try to replace the MAXI fuses under the hood that run the BECM. I feel like it might be those, because when the engine is hot everything starts to work
 
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ukadamwest said:
the fuse boxes on the P38 under the bonnet (hood) are notorious for failing after time here's where I got a replacement for mine from

http://www.ebay.co.uk/itm/Range-Rover-P38-V8-Petrol-Fuse-Box-with-fuses-AMR3375-with-Warranty/332376210319?_trkparms=aid=222007&algo=SIM.MBE&ao=2&asc=47510&meid=be0e167d92eb4f0fbeac1765da454459&pid=100005&rk=1&rkt=6&sd=263083065912&_trksid=p2047675.c100005.m1851
Click to expand...
Thank you sir! I'm going to do some track-and-reporting. Just got some blue MAXI fuses, that run the BECM and I will check with that first. If that reveals no joy I'm going to get that. Only £45.
 
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