kocr_bec Posted January 29, 2013 Share Posted January 29, 2013 Hi everybody, Long time I came to this forum. My Disco was not driven with for about two weeks because of a fuel leakage (one of the rear four tubes between filter and fuel tank). When I started her after a couple of times after fuel leakage was repaired the front fog lights were flashing very fast and the central locking was completely unpredictable (I think). After about two hours, she behaved normal again. This morning after a very rainy night I had the same problem. Any help? Probably electronic problem? Guess: Valeo BCU got water inside? Please confirm or other idea's .... Where is the BCU located ? Thanks in advance, Koen Quote Link to comment Share on other sites More sharing options...
SteveG Posted January 29, 2013 Share Posted January 29, 2013 I'd start by charging your battery properly. Erratic electronics are a symptom of low battery voltage. This at least eliminates this. Quote Link to comment Share on other sites More sharing options...
BogMonster Posted January 29, 2013 Share Posted January 29, 2013 Random electrical happenings like that usually point to the IDM (the brain inside the back of the fusebox) having got water in it. It may depend on whether your vehicle is LHD or RHD but on a RHD vehicle it is in the compartment under the steering wheel and you need to disconnect the battery and take the whole fusebox out, there are loads of multiplugs going into the back of it and it is a fiddle to get out. Take the cover off and my bet is that you will find a corroded mess on the circuit boards inside. If everything is still working when it is dry, you might get away with finding and fixing the water leak, but all the ones I have seen had permanent problems and needed a new fusebox, which is expensive. Flashing lights, random central locking actions etc all point to this being the problem. It's often/usually a leaking windscreen letting water in around the bond, but I had a water leak in mine which was a cross-threaded screw on the bonnet hinge, which took me three months to find! Quote Link to comment Share on other sites More sharing options...
kocr_bec Posted January 30, 2013 Author Share Posted January 30, 2013 Thanks guys The battery seems ok: 12,7 V I 'll have a look at the brain behind my fuse box then .... :-( If the sunroof is also operated from that brain then it could be the reason because quiet a period already (and nobody in my family believes me) at random moments I found the Disco with an open sunroof. Keep this post updated when having result ... Koen Quote Link to comment Share on other sites More sharing options...
BogMonster Posted January 30, 2013 Share Posted January 30, 2013 Yep, that's possible, and I expect the sunroof is operated through there. Most things that are fused and/or switched by a relay go through there, so locking, windows, lights etc. Quote Link to comment Share on other sites More sharing options...
kocr_bec Posted January 31, 2013 Author Share Posted January 31, 2013 Unplugged all cables on the back of the fuse box. Got it out of the car. Removed all fuses and a couple of relays. Opened the gray plasic box (12 clips, used 12 little forks to hold them ;-) The circuit board looks like a new one. Lucky for the board but not for my troubleshooting .... :-( Anyway I will apply some contact spray and dry it with compressed air ..... Only option is to rebuild it and test it .... ???? Quote Link to comment Share on other sites More sharing options...
kocr_bec Posted January 31, 2013 Author Share Posted January 31, 2013 Put everything back in place and had the connectors reconnected. Changed a 40A fuse (#5 under bonnet, for Cooling Fan(s)) Changed a 15A fuse under steering wheel (brake light) Hooked up the battery again. Got some water in the face from the head light washers :-) Hazard lights started flashing. Closed bonnet and doors again They didn't reopen. Had to use the key. Again indicators started flashing (like intruder alarm goes off without sound) When trying to start engine M+S (auto gearbox flashing) and a "D" came up on the dashboard with some strikethrough (like: forbidden or unable to drive) Did not see the front fog lights flashing Maybe I should also notice that just before this misery began I changed the fuel lines from fueltank to filter. When I started the engine I forgot to connect the connector on top of the fuel tank (pump and level ?). Reconnected it and the Disco drove perfect during a test drive. When I stopped the engine and tried to restart the misery began ... Quote Link to comment Share on other sites More sharing options...
kocr_bec Posted January 31, 2013 Author Share Posted January 31, 2013 Could the inertia switch have something to do with the problem? And how do I reset it ? The manual talks about starter switch in "position II" and opening and closing the driver's door ... ???? I will go outside and press the thing ... Quote Link to comment Share on other sites More sharing options...
kocr_bec Posted February 1, 2013 Author Share Posted February 1, 2013 It is not the inertia switch. An hour ago, a friend with a Rovacom computer came by to read the computers from my Disco. Analysis: The only computer that talks with the Rovacom is the ECM (Engine Control M....) which is sitting next to the battery All other computers like alarm, BCU, Auto Gearbox, ... refused to talk with the Rovacom. After taking out the start relay we manually connected the start engine and the td5 started and seemed to get fuel. Taking away the bridge cable made the engine to stop or might also be a fuel restart that the engine was running on. A second try made the eninge go round but without success. No more fuel. The Rovacom again connected made the ECM say it didn't get the signal to fire the engine up from neither BCU or alarm ..... !!! I'm stuck ... Someone knowing if the alarm is sitting in the BCU or is a module apart ? Koen Quote Link to comment Share on other sites More sharing options...
BogMonster Posted February 1, 2013 Share Posted February 1, 2013 It's all in the BCU as far as I remember, but it's a while since I did this stuff now Quote Link to comment Share on other sites More sharing options...
kocr_bec Posted February 3, 2013 Author Share Posted February 3, 2013 It's all in the BCU as far as I remember, but it's a while since I did this stuff now Does this mean I HAVE to go to the dealer ? Quote Link to comment Share on other sites More sharing options...
kocr_bec Posted February 5, 2013 Author Share Posted February 5, 2013 According to http://forums.lr4x4.com/index.php?showtopic=75950 there was a slight possibility that water had gone into the ultrasonic volume control in the interior. Bad luck again for me: My Disco does not have these sensors :-( The road to the dealer is about the only solution that is left. I am very afraid for the bill !!! Quote Link to comment Share on other sites More sharing options...
Niamh Posted February 6, 2013 Share Posted February 6, 2013 It is not the inertia switch. An hour ago, a friend with a Rovacom computer came by to read the computers from my Disco. Analysis: The only computer that talks with the Rovacom is the ECM (Engine Control M....) which is sitting next to the battery All other computers like alarm, BCU, Auto Gearbox, ... refused to talk with the Rovacom. Are you sure all the TD5 modules are installed on the Rovacom? Niamh Quote Link to comment Share on other sites More sharing options...
kocr_bec Posted February 8, 2013 Author Share Posted February 8, 2013 Are you sure all the TD5 modules are installed on the Rovacom?Niamh I am pretty sure because my Disco has already been checked with the same Rovacom in the past ! Thx for helping me so far guys Quote Link to comment Share on other sites More sharing options...
kocr_bec Posted February 11, 2013 Author Share Posted February 11, 2013 update: The Rovacom-friend started thinking backstage. Today he told me that the BCU is not sitting behind the fuse box (attached to it) but behind the glove box compartment. He was right. With a lot of patience I removed the BCU (4 or 5 connectors and very short cables ... :-( ) I removed the BCU box and opened it. The main IC (an SMD) has 2 or 4 damaged pins .... !!!! Pictures will follow. Further investigation will follow tomorrow. Hope I 'am on the right track. Next problem: What caused those pins to burn or melt or .... ? Rest of the circuit looks allright and as well very clean like other board (which then should be the ICM) Quote Link to comment Share on other sites More sharing options...
kocr_bec Posted February 18, 2013 Author Share Posted February 18, 2013 Resolderded 2 pins. The Disco started and drove for about 200 meters. De strikethrough "D" as in Drive next to the mileage started flashing again together with M+S from auto-gear box. Only in position "D" the car wanted to move. "R" didn't function. Turned engine off, but was not able to start it again. Had to push the Disco back home (with 3 people). Removed the BCU, one pin seemed to be disconnected again. Resoldered but without success !! When I push the remote to open, fog lights flash short. Close works fine. Have to open the car with the key. Then the fog lights flash continuously until I put in the key into the ignition. Like an alarm without sound. Strikethrough "D" appears an M+S start flashing. Car doesn't start Quote Link to comment Share on other sites More sharing options...
kocr_bec Posted February 18, 2013 Author Share Posted February 18, 2013 Reopened BCU. Island for broken pin to solder upon has broken .... Will start to look for thrown away motherboard from BCU to find out where track is going to. It disappears under this chip so I can not see where it is going. Then replace it with wire .... Quote Link to comment Share on other sites More sharing options...
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