| Author | Message | ||
     lucien mc fadden Experienced User Username: lucienm Post Number: 17 Registered: 7-2005 |
Greetings all ! :} Today i attempted to do the window modification on my 76 rolls LRE25894 as per Richard Treacys'instructions.I had the motor overhauled about a year ago and had to pull it out again as the brushes were sticking. There is power to the modules (relays) and they click when the window switch is pressed--there is power to the motor when the switch is activated, with a meter i get almost 12 volts from each position on the relays and at the motor as well(when switch activated). BUT--no window movement(!) there are 2 wires going to the motor-yellow & yellow/black stripe--as well as what appears to be a green ground wire connected a a point where the motor bolts to the lift mechanism. Any ideas ? | ||
| lucien mc fadden Experienced User Username: lucienm Post Number: 18 Registered: 7-2005 |
my question too stupid? | ||
| Paul Yorke Frequent User Username: paul_yorke Post Number: 96 Registered: 6-2006 |
Lucien, It's tricky without being there. If you have a feed to the motor, then you must be lacking the earth. Make sure the earth to the relays is good. Undo one wire from the motor. Check both wires that should be attached to the motor for an earth when the switches aren't operated. I'm not sure what Richard suggested set up is but I guess it should be two earth's at rest. When the switch is operated in the up or down position, one earth should turn to a feed. A test light put across the two wires should light up when the switches are operated. Relays ( unless waterproof ) are not really a good idea in the door so cover them well and mount them terminals down. There's also more things to go wrong. No wiring mod will stop the brushes sticking. Try to operate the windows whenever you use the car or every couple of weeks. Do it when you return home though  Good luck. | ||
| Billy UK Unregistered guest Posted From: cpc1-epso1-0-0-cust154.hers.cable.ntl.com |
I have just this week installed this modification (on all but driver's door) and it works fine. Lucien, have you ensured the BRAKE solenoids are energised with the motor/s....? By the way, I have actually deleted the brakes as this ensures full 'power' goes to the motor/s and any slight dropglass movement I can live with, although that is just my whim.... (Message approved by david_gore) | ||
| John Kilkenny Experienced User Username: john_kilkenny Post Number: 49 Registered: 6-2005 |
Lucien, Have you included the diodes in the circuit ? If not, both relays will be energised when the switch is pressed and there will be 12 volts on each motor wire instead of 12 volts on one and 0 volts on the other. Otherwise re-check all the connections. Do not disconnect the brake solenoid as the window will certainly drop slowly under gravity when the switch is released. | ||
| lucien mc fadden Experienced User Username: lucienm Post Number: 19 Registered: 7-2005 |
Greetings All! :} connection to 1 of the diodes was faulty-everything is fine now,window goes up like a dream! :} Thanks everyone for your help! | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 1310 Registered: 4-2003 |
I'm glad that you sorted it as the fix should always work. Here is an extract from: http://homepage.swissonline.ch/Richard_Treacy/WindowLifts.html <<<<<<<<<<<<<<<<<<<<< Why the Diodes ? I have been asked this question several times now, so here is a general reply: The configuration that I have chosen is no accident, and will only work with the diodes in place. On the front passenger's door, it is impossible to delete the diode without running a new wire through to the door innards. In that case, you would fit two relays anyhow, as on both rear doors. In each case, the relay picks up when the potential difference between the control wires is 12V and of the correct polarity. The diode is the simple logic device to allow the relay to pick up only when it should, and also to protect the relay suppressor as explained below. With a reconfiguration, it is marginally possible to delete the diodes on the rear doors only, but it is unwise. Diodes only cost 10c or so anyhow. Any general purpose power diode like a 1N4001, 1N4004, 1N4007 or EM513 is fine. Let me explain. Most Bosch relays, and other brands too, use a freewheel diode as a suppressor (stops voltage spikes which cause radio noise and damage electronics). When even the substantial cigar lighter power cable is used as a trunk feed as on the rear doors, there is a certain voltage drop on load. This trunk wire would need to be used as the reference voltage for both relays on the + coil terminal in a reconfigured setup. This means that the relay not being activated would have a reduced reference voltage while the window is working or the cigar lighter is being used. As the other side of the coil would remain at +12V as fed unloaded from the driver's door, the relay coil would have a slightly reversed voltage. Anything above 0.6V reversed will burn the freewheel diode inside the relay to bits as it starts to conduct. Given that you expect a voltage drop of up to 2V, the Bosch relay would not survive. Even using a cheaper bipolar relay with a conventional suppressor, it would be very bad practice to allow this reversed voltage situation. In worst case, both relays may try to pick up, and then give either no function or buzzing. Now, you would not want the windows to shift or fail just because someone presses the cigar lighter would you ? Conceivably, other loads (headlamps, fans etc) could cause the same effect. Definitely, winding two windows at once would be risky without the simple insurance of the diodes. It's best to fit the diodes, even if you decide on a different schematic. | ||
| Jeffrey McCarthy Prolific User Username: jefmac2003 Post Number: 174 Registered: 5-2007 |
Richard (or anyone), I am slightly confused about the white wire (0.7sq mm low power) used in this mod. The red & the black are obvious from the diagrams but where is the white used? Is it the feed with the diode on it? Also why such thin wire - I'm sure there's a good reason but how critical is it? I'm not very familiar with wire gauges but I have some white wire about the same gauge as the yellow/yellow black wires already there. No rush for this info - I'm installing new speakers in all 4 doors over the next few weeks so it's an opportunity to do the mod while I have the door cards off. Incidentally for the front passenger window I intend to run a cable spliced from the cigar lighter circuit - perhaps from the centre console with an in-line 30amp fuse under the dash and accessible from the cubby hole. Is this a bad idea? If anyone has photos of this mod in place perhaps they would be useful too. |
