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Discussion Starter #1
Hi all,

Rather than adding to my other post on the EAS I was wondering if anyone knew which terminal on the BECM / EAS ECU signals the door and tailgate inhibit. If so is there a way I can test it with a meter to check to see if it is actually signalling the EAS ECU to inhibit. The door open signal is working on the dash so I am assuming the door units must be working or is there another output from the door outstation that I can check? If I get a signal from the BECM to the ECU it may lead me to the ongoing fault with the EAS (as per Marty's thoughts) I have covered pretty well everything else on the system.

Thanks

Chris
 

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Pin 34 on the EAS ECU is shown as "Door Input". Don't know if that helps at all!
Connects to C112 pin 3 BECM (side tail door open) and
C118 pin 5 Delay timer
 

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Discussion Starter #3
Cheers for the info, any idea if I can check for or what current the signal is with a meter, or is it a pulse signal, I would think it would be a current

Chris
 

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Pin 3 at the BeCM is grounded when the tailgate is open. I think you will find all hood, doors and tailgate/hatch are ground signals either from source or from the outstations.
 

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"Cheers for the info, any idea if I can check for or what current the signal is with a meter, or is it a pulse signal, I would think it would be a current"
Pin 3 at the BeCM is grounded when the tailgate is open. I think you will find all hood, doors and tailgate/hatch are ground signals either from source or from the outstations.
That's interesting RRTH. As P3 BECM is connected to P5 Delay timer that takes that to ground too, thus freezing the EAS, I assume.

I'm no EAS guru Chris, unfortunately- just getting info from the circuit diagrams and pinout info :)
 

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I happened to have the BeCM SID open checking into a frayed wire. :)

If you don;t have a copy already it does make for light reading when you have run out of sedatives. I've posted it a couple times before.
 

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Ahhhh, hold on... in digging a bit further into the pin tables I found a notation that PIN 3 send signal to EAS ECU. Ground when door or tailgate open, otherwise battery volts.


:twisted:Gotta love when info is not carried consistently between charts.
 

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THanks for the link. I haven;t fingered out how to link from mobile. :cry:
 

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Discussion Starter #11
I don't suppose there is one for the EAS ECU :)

Cheers

Chris
 

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Wow, forgot about that one!
These SIDS are hard to track down. Perhaps the files could be uploaded to the server and linked from the FAQs sticky, like RAVE download fr'instance. That way no-one will ever be able to find them :)
I see we can upload links and pictures, but not files unfortunately.
 

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Discussion Starter #16
Again, many thanks chaps, I now know a little more of what to start checking

Cheers

Chris
 

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Discussion Starter #17
I have been browsing the links given and notice that the pinout given (34 notably) differs from Storeys pinout, mind you it does mention that it is not known. I assume that as Storey has rather a lot of background on the unit that 34 is the inhibit signal line. I will find out tomorrow. :)


Cheers

Chris
 

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1995-2002 Range Rover P38A
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I've got SID's for the BECM, EAS, Bosch Motronic, and Automatic gearbox. Haven't found any for the HEVAC, ABS, or other systems yet.

As mentioned, the door inhibit line should be showing 12V (ish) when all of the doors and tailgate are closed. When one of any of the doors or tailgate are opened (the BECM monitors all 5 of these inputs) it will ground the door inhibit line to let the EAS ECU know that something has been opened. The EAS ECU doesn't know (or care) which door/tailgate have been opened - it just gets told that one of them is open and to freeze auto levelling/height changes.

The wire at the EAS ECU is pin 34, and should be either Purple/Grey (as listed in EAS SID) or Purple/Orange (as listed in RAVE). With a multimeter set to DC Volts, between that wire (positive probe) and a ground point on the vehicle, you should have 0V with a door open and 12V with the doors/tailgate closed.

You should also have the same at the EAS Delay/Timer relay - pin 5 (Purple/Orange) should read the same. As should Pin 3 of C112 that has already been mentioned.

If the voltage toggles at the BECM end, but not at the delay timer/EAS ECU then there is an issue in the wiring. Also, it is worth testing the BECM end with the connector at the BECM DISCONNECTED - as if there is a short in the wiring to the EAS ECU then it could be possible that it is permanently holding the inhibit line to ground or a voltage (depending on what it's shorted to!)

If you get the correct reading at the BECM with the connector unplugged, and with it plugged back in, but not at the ECU/delay timer, then it could be there is a break in the wiring (it is directly wired through the body loom, so no connectors half way that could be corroded) but the place to check would be to trace the splice where the wire splits to the delay timer and EAS ECU.

I also think that if the wire is disconnected, then the input at the EAS ECU will just be a 'floating' voltage, so the ECU will always think that the doors are closed (had the issue on a mates one where a pin has come adrift and it was changing height with a door open, and found a loose pin in the BECM connector). So the ECU will need a solid ground connection (as the BECM would normally supply) for it to activate the inhibit.

If the wiring checks out, and the inhibit signal toggles properly at the BECM, and the EAS ECU and delay/timer relay - then I do wonder if it comes back to your EAS ECU being at fault.
 

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Discussion Starter #19
Cheers again all,
Hmm, no signal at pin 3, explains the inhibit issue I guess, any info on where is the signal coming from to get to the BECM, the signal is getting to the dash but not to pin 3. I would have thought that these two would be from the same signal point?

Cheers

Chris
 

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How do you mean the signal is getting to the dash, but not to pin 3?

There are 2 different inhibits we are talking about.
1) the door inhibit which comes from the BECM to the EAS ECU and the delay/timer relay. This is the one that ends up on Pin 3. The BECM outputs this, and decides on what the inhibit should be (12V - ok, you can adjust vehicle height, or GND - A door is open, freeze vehicle height) based on 5 inputs to the BECM - one from each door ajar switch in the 4 door latches, and the 5th from the tailgate open switch in the tailgate latch. If ANY of the 5 inputs show as the door/tailgate being 'open' then the BECM will tell the EAS ECU to freeze.
2) the ride-height inhibit switch. This is the one on the dash, and doesn't connect to the BECM at all. As I've mentioned before, this goes from the switch on the dash, directly to the EAS ECU. The only connection this switch has from the BECM is to power the telltale lamp, and that also splits off to power the ride height adjustment switch.

Both of these inhibits run into the EAS ECU on different inputs, so don't join anywhere or are controlled together at any point.

Marty
 
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