View Full Version : Cant get compressor to run
wayneg
21st March 2011, 07:29 PM
EAS shut down today. Reset and compressor not running. Checked fuses in fusebox ok. Checked Relay, OK, Shorted relay, Compressor runs, checked pressure switch , open circuit, good. Thermal cutout good With eas software called for compressor to run, runs ok. Checked normal operation and compressor does not run.
Dont think the EAs software is fully linked to the system, cant get any movement on the second row of moving numbers.
What now? any more tests for the EAS ECU or Driver block?
Anyone know more about jumping pins 1 and 8 on the ECU. I understand 1 is live and 8 goes of to fire the Compressor but not sure
RR P38
21st March 2011, 08:36 PM
You are going pretty well with the illumination of potential problems.
When you say you checked the relay did you do both?
The one under the bonnet in the fuse box (expensive from memory $70) and the one under the passengers seat.
It sounds like everything is lined up but no signal to go is forthcoming.
Could it be the dumb computer that runs the compressor?
I think the computer is unlikely.
You are not in EAS fault mode on the dash are you?
RR P38
21st March 2011, 08:49 PM
Stick with investigating under the passenger seat
I hope you get of your bump stops soon:(
wayneg
21st March 2011, 08:56 PM
I got it unlocked ok and can manually pressurise the system so still mobile and semi functional. If it persists I will just bang on the bypass valves till sorted. I have not checked the under seat relay so thanks for pointing that out.
Just found this from Storey Wilson after looking for relay probs so will post it here so I can find it again
First Question always is; What are you getting back in the Rx buffer. Until you get only FF during communications idle, then none of the operations with the EASunlock software will work.
If you get FF and 1 in the Rx buffer, you are on the wrong comm port. (You are on a internal laptop loopback port)
If you get nothing back in the Rx buffer during communications idle, then your USB 2 Serial adapter is not working or your cable is wrong, or the Range Rover wiring is suspect. (No communications at all; Tx and Rx are bad)
If you get 28 or 80 back in the Rx buffer then your USB 2 Serial adapter might stil be acting up, or your cable might be incorrect, or the Range Rover wiring might be suspect or the EAS delay relay might be suspect. (Some communications; Tx and Rx are working; EAS power reset is not working)
Overall, make sure you have drivers installed for the USB 2 Serial adapter. Make sure you have the windows device manager open when you plug the USB to serial adapter in. Watch the new comm port appear in the windows device manager. When the comm port appears use that inside the EASunlock software configuration for the comm port number. You can also shift the comm port number that the USB 2 serial adapter emulates. Changing the enulated serial port can sometimes also cause the adapter to suddenly start working.
Make sure the cable is correct. I think the cable is the most likely cause of the lack of communications. You have tried a laptop with a built in RS232 so that is uaually a good working test. But that failed. I think your cable is bad and then next I would inspect the OBDII port wiring harness by droping the footwell pannel. Then I would inspect the EAS ECU C117 Wiring harness for damage.
Wiring harnesses in the Range Rover can go bad. I usually ask if the heater core has ever leaked. If you have had a coolant leak in the heater core, then the OBDII port and some of the wiring harnesses that are next to the heater core are suspect. But check the OBDII port first it is easy to get to and can be cleaned with some contact cleaner.
Next I inspect the EAS ECU. The EAS ECU is located under the Left hand seat. Some pannels will need to be removed and you will also need a medium sized phillips screwdriver with a very very short handle. The EAS ECU is located on the bottom. Use a flat head screw driver to pop the EAS C117 multiplug connector off. Inspect the wiring harness and the C117 pins. If the connector has ever been opened, make sure that the plastic retaining combs are still on either side of the C117 connector. The plastic retaining combs keep the pins in contact with the EAS pins. Some souorces also say that the rubber gasket on the C117 connector is too thick and prevents the connector from seating correctly with the EAS computer. So try removing the rubber gasket for testing. Long term, you can remove about 1/3 of the thickness of the gasket with sand paper and refit.
Also inspect the EAS delay relay. The EAS delay relay is located under the left hand seat on the outer side of the seat. It is a black tall rectangular relay, which has its own wire harness and is attached to the seat subframe with a rubber groumet. Make sure that the wires are in good shape. The EAS is power cycled during the EAS communications protocol. If you can not hear or feel the EAS delay relay clicking when you press "initialize", then it might be bad. Try replacing it.
Can anyone sticky this thread answer? I do not want to type it all again.
__________________
Storey Wilson
RSW Solutions LLC
www.RSWsolutions.com
RR P38
21st March 2011, 09:50 PM
I am a complete Dick that relay i gave you the part # for is in fact for the brake booster pump i must have had 1 too many beers and forgot what the problem was.
As your last post states look into things under the passengers seat.
PaulP38a
22nd March 2011, 02:18 AM
Wayne - I am confident that you simply have a comms problem between the PC and the OBDII port. I trust you are NOT using a EAS Unlock Cable and USB-Serial Adapter from Hard Range?
Mine work, and are recommended by Storey Wilson. PM me your address and I will send you a set (no charge, you've helped me out a few times in the past). If you like them I know you will do the right thing...
AULRO P38 Owners SPECIAL
EAS Unlock Cable, USB-Serial Adapter, driver and EAS Unlock software on CD, plus Express Postage to anywhere in Australia for $44 inc GST (payment via PayPal to sales@hardrange.com or direct deposit only).
Offer extended to all members with paid AULRO subscriptions. Remind me in your PM or e-mail to info@hardrange.com
Cheers, Paul.
wayneg
22nd March 2011, 02:52 PM
Paul, have sent $44 via paypal for the lead. Never been totally happy with mine anyway
Things seem very odd. The software unlocked the system and the suspension seems to work fine. I can force the pump to run with the software but it wont run under normal conditions. I have been able to get faults up on a couple of occasions but most times no response. I can feel the relay click when I initialise the software but no figures in left column. Also the car seems to know that theres something plugged in but usually all 4 eas lights come on and the 55klm warning comes on. This is not happening in a solid fashion, comes and goes with lots of beeping
Would still like to know if shorting pins 1 and 8 on the ecu plug will force the compressor to run or have I already proved good but getting the compressor to run via EAS unlock
PaulP38a
22nd March 2011, 09:41 PM
On the EAS connector under the passenger seat, pin 1 is power and pin 8 is the compressor. Good write-up here suspump (http://rangerovers.net/repairdetails/airsuspension/suspump.html#compact)
Haven't needed to do this myself in a couple of years, but it did work, and I think I still have the 4-way "pigtail" and reference sheet in my glove-box should I ever need it again.
Will send your AULRO EAS Bundle tomorrow :)
Also check the pins and rear connections on the OBDII port to make sure they are clean and make good contact.
Cheers, Paul.
wayneg
22nd March 2011, 10:22 PM
Thanks for that, have read that before but somehow could not find it when needed. My understanding now is that if 12v appears at pin one on the ECU plug with ignition on it proves the delay relay is Good.
I will check the obd2 connector and wait for your lead as its looking like a comms issue as you suggested.
PLR
22nd March 2011, 11:41 PM
Hi ,
www.rover-renovations.com/ (http://www.rover-renovations.com/) is where the making of my pigtails and instructions that live
in the car came from .
PaulP38a
23rd March 2011, 12:00 AM
Hi ,
www.rover-renovations.com/ (http://www.rover-renovations.com/) is where the making of my pigtails and instructions that live in the car came from .
specifically, Dennis' how-to is at Rover Renovations Knowledge Base (http://www.rover-renovations.com/kb_results.asp?ID=27)
I'd forgotten that Dennis did a write-up on this too.
Cheers, Paul.
wayneg
23rd March 2011, 05:13 PM
Removed the obd11 plug on the car and as suggested there was corrosion on the pins. I think this might be an issue if the aircon drain gets blocked and it overflows into the passenger foot well. This was the case in my car when I got it. Gave it a good clean before refit ( the obd11 plug, the air con was sorted long ago). Removed EAS ECU, checked plug ok , sprayed with switch cleaner than back again. Dug out old Toughbook laptop and it fired up 1st go. Connected serial cable to car and laptop. Started EAS Unlock, Initialised, cleared faults, read faults.... NONE. GOOD IDLE, Removed cable, started car, Compressor singing away:D
As a special treat I fitted new insulation mounts to the compressor.
For those who moan about the EAS, whilst I was messing with this issue I was still driving the car every day as usual, running the compressor via a jumper for 5 mins in the morning. Cost to fix, ZERO however I did elect to buy a new lead as I am sure mine is Suspect
RR P38
23rd March 2011, 08:10 PM
Good work there then buddy.
As you say there is a lot of moaning about the EAS. Really it is a basic system.
I have interrupted the power supply to the Brain on mine and i have a switch on the dash i run my compressor only once or twice a day and turn the system off. This saves any unnecessary wear on the system.
wayneg
23rd March 2011, 10:50 PM
Really it is a basic system.
I have a switch on the dash I run my compressor only once or twice a day and turn the system off. This saves any unnecessary wear on the system.
We are on the same wave length, I was thinking this all along , so simple to override it if that`s the way you want to go.
I like to keep mine as stock as practical but as you are a long time owner I understand your stance
PaulP38a
24th March 2011, 12:17 AM
Good work there then buddy.
As you say there is a lot of moaning about the EAS. Really it is a basic system.
I have interrupted the power supply to the Brain on mine and i have a switch on the dash i run my compressor only once or twice a day and turn the system off. This saves any unnecessary wear on the system.
I'm guessing you have cut in to pin 1 on the connector? Clever :D
I have been pondering a switch inline to the EAS Delay Timer to disable the EAS when doing silly stuff off-road. After dislodging my rear right height sensor arm twice in recent times and opting to pull out the EAS Delay Timer rather than crawl under the car in the mud, I think a switch on the dash would be more convenient than pulling the timer out.
Next switch on my wish list is to disable the ABS ;)
Cheers, Paul.
RR P38
24th March 2011, 10:34 AM
I have run the wire up from the EAS ECU into the spare switch spot next to the cruise control on off (above the clock)
I used a switch that is lit when the EAS is on and unlit when it is off.
I did have a switch under the seat, what a pain that was.
It is a pretty good retro fit it pretty much looks like a part of the dash i carefully (drilled)cut the blank switch cover it is a very neat job.
With the resale value of a P38 im not to worried about keeping it original.
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