Keithl Posted March 14, 2020 Share Posted March 14, 2020 So could a failing(ed) engine earth strap (Nick's favourite) cause the same momentary loss of connection? Keith. Link to comment Share on other sites More sharing options...
Robinhood Posted March 14, 2020 Share Posted March 14, 2020 Given the advice, the integrity of all the vehicle battery connections is certainly worth a check. As I said above, my expectation on your age of vehicle is that the D+ signal to the Electroblock will be a fairly simple circuit, and probably via direct alternator connection (given you are pre-Canbus, for which less simple arrangements apply - e.g X/290). It is unlikely there is anything in your circuit to cause a problem, but it may well be worth checking that alternator to EBL connection. Those done, then there is little else to do but refit it, and hope all is OK. Keithl - 2020-03-14 7:48 PM So could a failing(ed) engine earth strap (Nick's favourite) cause the same momentary loss of connection? Keith. ...always possible, but (without checking) I think this concern was mainly expressed around X/250 and X/290 models? Link to comment Share on other sites More sharing options...
plwsm2000 Posted March 14, 2020 Share Posted March 14, 2020 BruceM - 2020-03-14 11:00 AM Specifically Re: plwsm2000 - 2020-03-13 5:24 PM As mentioned in my earlier post above, the Schaudt diagram shows the D+ output from the EBL driving the "Battery cut-off" (split charge) relay that is external to the EBL. Before you plug in the repaired EBL, it may be worth checking that the split charge relay coil has not gone short circuit. This may have caused the original damage to the D+ control circuit. That is why I was interested to know if the split charge function was working ok. Presumably you’re referring to the D+ Base output on pin 2 of block 1 (see diagram in picture below). I’ll have to trace the wiring to see where this goes in order to track down the external split charge relay. What would be the purpose of this relay, ie what device would it be connecting/disconnecting to the engine electrical power plant only when the engine is running? Bruce, No - I think the D+ on pin 2 socket 1 would be an output for the fridge to switch over to 12V (if used) . I was referring to the "Battery cut-off relay" as highlighted below. I would be concerned if there was a short circuit on the D+ OUTPUT (on anything connected to either the A1 terminal or to pin 2 of socket 1) that could damage the D+ circuit again. The spilt charge relay is often mounted near to the starter battery as it uses some fairly thick cables to connect the two batteries together. It may be driven from the D+ directly and not from the EBL as per the diagram. It is probably easier to see if the EBL D+ outputs have any wires connected to them. Link to comment Share on other sites More sharing options...
Robinhood Posted March 14, 2020 Share Posted March 14, 2020 plwsm2000 - 2020-03-14 8:37 PM No - I think the D+ on pin 2 socket 1 would be an output for the fridge to switch over to 12V (if used) . ...Indeed. The signal on that pin is used to feed the AES fridge PCB, and the logic therein which determines source switching. (for a non-AES fridge, it will be unconnected). Link to comment Share on other sites More sharing options...
BruceM Posted March 16, 2020 Author Share Posted March 16, 2020 plwsm2000 - 2020-03-14 8:37 PM I was referring to the "Battery cut-off relay" as highlighted below. I would be concerned if there was a short circuit on the D+ OUTPUT (on anything connected to either the A1 terminal or to pin 2 of socket 1) that could damage the D+ circuit again. The spilt charge relay is often mounted near to the starter battery as it uses some fairly thick cables to connect the two batteries together. It may be driven from the D+ directly and not from the EBL as per the diagram. It is probably easier to see if the EBL D+ outputs have any wires connected to them. I have a view on the battery cut off relay and I’d appreciate your opinion. The block diagram for the EBL 99 indicates the battery cut off relay to be external to the EBL. However this makes little sense to me. There are three connectors on the back of the physical EBL (you’ll note that they are near the battery cut off relay on the block diagram). The three connecters are Starter Battery +, Habitation Battery + and Habitation battery – . The battery cut off relay is shown to exist after this point. Furthermore, if we refer to https://www.wvopzeeland.nl/EBL99C_BA_EN.pdf you will note that the battery cut off relay is listed as one of the EBL’s functional relays (page 4). So I’m thinking that the fact that I can’t spot an external battery cut off relay is because it’s inside the EBL and consequently its functionality will have been verified during the repair process. Link to comment Share on other sites More sharing options...
Robinhood Posted March 16, 2020 Share Posted March 16, 2020 BruceM - 2020-03-16 12:12 PM So I’m thinking that the fact that I can’t spot an external battery cut off relay is because it’s inside the EBL ........ Bruce, didn't respond before as I've always thought that the relay was internal, and just passed on the question. The relay is shown on the block-diagram inbound of the EBL main battery connections. These are directly on the rear of the unit (and it is easy to see the correlation between the block-diagram external connectors and the picture here): https://i.ebayimg.com/images/g/NyEAAOSwyjBW4VMe/s-l1600.jpg This is, admittedly, a picture of an EBL29, but it is very much the equivalent of the EBL99. I would be almost certain that the relay in question is internal, and that the positioning on the block diagram is for space and clarity reasons. Link to comment Share on other sites More sharing options...
BruceM Posted March 16, 2020 Author Share Posted March 16, 2020 Many thanks, that's saved me some head scratching. Link to comment Share on other sites More sharing options...
Robinhood Posted March 16, 2020 Share Posted March 16, 2020 ...and, edited quickly from a German forum (so apologies for the quality). The dotted line represents the PCB. The relay in question isn't board mounted, but is mounted directly on the inside of the case. (You can see the offending article in the bottom right of the picture ;-) ) Edited to add better picture - snip from forum left as attachment as it has the (transalated) German wording. https://www.ducatoforum.de/forum2018/index.php?attachment/39142-ebl99-jpg/ Link to comment Share on other sites More sharing options...
BruceM Posted March 19, 2020 Author Share Posted March 19, 2020 Just a postscript to say that the repaired EBL was fitted and everything appears to be working as required although the fridge is yet to be tested for on extended period on 12v – that test will come later and will be the clincher on whether or not the fix is permanent. As a precaution the vehicle earth connections were checked and found to be fine. The starter battery connections were also cleaned up and remade even though they appeared on inspection to be clean. Many thanks to all for the assistance. Link to comment Share on other sites More sharing options...
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