Re: [MBZ] 124 rear defroster timer
Is it the challenge of getting it to multi-task? For me, absolutely! -- Jim
[MBZ] 124 rear defroster timer
Meanwhile, I'll plug charger into cig lighter. Wilton
[MBZ] 124 rear defroster timer
Thnx, Marshall. Just had a thought that I may be able to use defroster circuit to charge mobility scooter in trunk; I'm using cig lighter socket now. 'Think I read in owner's manual coupla days ago that a timer cuts power to defroster after 20 min. Be it 20, 15 or whatever time, if the timer regulates other things, too, I can't use that circuit for charger. Wilton
Re: [MBZ] 124 rear defroster timer
Thnx, Marshall. Just had a thought that I may be able to use defroster circuit to charge mobility scooter in trunk; I'm using cig lighter socket now. 'Think I read in owner's manual coupla days ago that a timer cuts power to defroster after 20 min. I have a similar idea to run a travel cooler in the back of our SL's, the plug is accessible even. But the timer was really a pain to keep track of. I've got some circuit ideas, but it'll take a session or two of reverse-engineering of the timer to see if it's practical. May never happen. -- Jim
Re: [MBZ] 124 rear defroster timer
Do 123s have the same sort of defrost timer? -- Casey Olympia, WA Biodiesel: I drive in a persistent vegetative state '87 300TD intercooler (211k) '84 300D (210k) Gashuffer: '89 Vanagon Wolfsburg Edition (187K)
Re: [MBZ] 124 rear defroster timer
Do 123s have the same sort of defrost timer? Yes, I think everything since mid 114/115 does. -- Jim
Re: [MBZ] 124 rear defroster timer
OK Don wrote: Tap the line close to the defroster - run the wire to a SPDT switch, run one side back to the defroster, anjd the other to the charger --- then you can use the defrost switch on the dash to time either one. Not sure but the load (resistance) of the thing being timed MIGHT influence the time. When the load of the turn signals is halved, they flash twice as fast (and that's controlled by the combination relay timer). Marshall -- Marshall Booth (who doesn't respond to unsigned questions) der Dieseling Doktor [EMAIL PROTECTED] '87 300TD 182Kmi, '84 190D 2.2 229Kmi, '85 190D 2.0 161Kmi, '87 190D 2.5 turbo 237kmi
Re: [MBZ] 124 rear defroster timer
Ah - good catch! Maybe just fire a relay with the defroster - run them both at the ame time? On 2/14/06, Marshall Booth [EMAIL PROTECTED] wrote: OK Don wrote: Tap the line close to the defroster - run the wire to a SPDT switch, run one side back to the defroster, anjd the other to the charger --- then you can use the defrost switch on the dash to time either one. Not sure but the load (resistance) of the thing being timed MIGHT influence the time. When the load of the turn signals is halved, they flash twice as fast (and that's controlled by the combination relay timer). Marshall -- -- OK Don, KD5NRO Norman, OK '90 300D 243K, Rattled '87 300SDL 290K, Limo Lite, or blue car '81 240D 173K, Gramps, or yellow car '78 450SLC 67K, brown car '97 Ply Grand Voyager 78K Van Go
Re: [MBZ] 124 rear defroster timer
OK Don wrote: Ah - good catch! Maybe just fire a relay with the defroster - run them both at the ame time? I thought his goal was to *not* have the charger be on a timer, but to have it run continuously once switched on.
Re: [MBZ] 124 rear defroster timer
Not sure but the load (resistance) of the thing being timed MIGHT influence the time. When the load of the turn signals is halved, they flash twice as fast (and that's controlled by the combination relay timer). With no other evidence than a vague idea of what the circuitry might be inside the relay, I don't believe that this is going to be a problem. It takes extra circuitry to make the flasher be load-sensitive (as opposed to the ancient thermal flashers that predate the electronic ones). To permanently disable the timer would probably require no more than shorting a capacitor inside the timer module, but again I have no factual basis for this belief. This may or may not be something that could be done by our interested party anyway. My desire was to work out a simple hack to the relay that would disable the timer if the engagement switch were actuated and held on for a period of time, thus allowing for normal and abnormal use via the same system. In an SL (my target) selecting between the glass heater and something else is easy and obvious, by way of selective plugging in of various appliances. Would be different for any other vehicle. -- Jim
Re: [MBZ] 124 rear defroster timer
Jim Cathey wrote: Not sure but the load (resistance) of the thing being timed MIGHT influence the time. When the load of the turn signals is halved, they flash twice as fast (and that's controlled by the combination relay timer). With no other evidence than a vague idea of what the circuitry might be inside the relay, I don't believe that this is going to be a problem. It takes extra circuitry to make the flasher be load-sensitive (as opposed to the ancient thermal flashers that predate the electronic ones). To permanently disable the timer would probably require no more than shorting a capacitor inside the timer module, but again I have no factual basis for this belief. This may or may not be something that could be done by our interested party anyway. My desire was to work out a simple hack to the relay that would disable the timer if the engagement switch were actuated and held on for a period of time, thus allowing for normal and abnormal use via the same system. In an SL (my target) selecting between the glass heater and something else is easy and obvious, by way of selective plugging in of various appliances. Would be different for any other vehicle. Most of the timer circuits I've seen in '70s-'80s (even electronic ones) set the interval using the value of a resistor and capacitor - and when the resistance doubles (as it does when a light goes out) the time constant changes by the same amount. Marshall -- Marshall Booth (who doesn't respond to unsigned questions) der Dieseling Doktor [EMAIL PROTECTED] '87 300TD 182Kmi, '84 190D 2.2 229Kmi, '85 190D 2.0 161Kmi, '87 190D 2.5 turbo 237kmi
Re: [MBZ] 124 rear defroster timer
This seems to be over-engineering to me. why not just run a switched power wire of proper gauge back there and ground it to chassis? That's what the older 114/115 used. They added the timer as a safety measure, because the defroster is a serious draw on the charging system. The timer is set to the value that should just about do the job. Also, by being timed the system goes off with the key and doesn't come back on by itself, as would be the case with the simple switch. If the light were out on the knob and you forgot and left it on the defroster could seriously suck your battery down with time and short-cycle driving, and you would be completely unaware in the absence of disappearing frost. -- Jim
Re: [MBZ] 124 rear defroster timer
On Wednesday, February 15, 2006, at 11:08 AM, Jim Cathey wrote: That's what the older 114/115 used. They added the timer as a safety measure, because the defroster is a serious draw on the charging system. The timer is set to the value that should just about do the job. Also, by being timed the system goes off with the key and doesn't come back on by itself, as would be the case with the simple switch. If the light were out on the knob and you forgot and left it on the defroster could seriously suck your battery down with time and short-cycle driving, and you would be completely unaware in the absence of disappearing frost. -- Jim I understand all that. Isn't Wilton trying to rig a charger for his electric chair? As I understand you have a different purpose for the hijacked current. Perhaps Wilton can hardwire a timer or a sensor that switches off when fully charged. It seems that 15-20 minutes would not be enough time to fully charge a low battery. Johnny B. I Mac Therefore I am
Re: [MBZ] 124 rear defroster timer
He might wish to consider adding a solar panel in the back window ledge (it is a car rather than a wagon isn't it?)so that the trickle charger would help to maintain the car battery if it is going to continue to charge the scooter when the engine is not running. The other idea might be an inverter and one of the small chargers that have the zero float circuit so that it can be left on all of the time and will know when to shut itself off. Hope this does not duplicate previous info too closely. I know I saw thread on this a bit ago but did not pay enough attention then to know and recall what was said. Randy B -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of John Berryman Sent: Wednesday, February 15, 2006 8:17 AM To: Mercedes Discussion List Subject: Re: [MBZ] 124 rear defroster timer On Wednesday, February 15, 2006, at 11:08 AM, Jim Cathey wrote: That's what the older 114/115 used. They added the timer as a safety measure, because the defroster is a serious draw on the charging system. The timer is set to the value that should just about do the job. Also, by being timed the system goes off with the key and doesn't come back on by itself, as would be the case with the simple switch. If the light were out on the knob and you forgot and left it on the defroster could seriously suck your battery down with time and short-cycle driving, and you would be completely unaware in the absence of disappearing frost. -- Jim I understand all that. Isn't Wilton trying to rig a charger for his electric chair? As I understand you have a different purpose for the hijacked current. Perhaps Wilton can hardwire a timer or a sensor that switches off when fully charged. It seems that 15-20 minutes would not be enough time to fully charge a low battery. Johnny B. I Mac Therefore I am ___ http://www.striplin.net For new parts see official list sponsor: http://www.buymbparts.com/ For used parts email [EMAIL PROTECTED] To Unsubscribe or change delivery options go to: http://striplin.net/mailman/listinfo/mercedes_striplin.net
Re: [MBZ] 124 rear defroster timer
I understand all that. Isn't Wilton trying to rig a charger for his electric chair? As I understand you have a different purpose for the hijacked current. Perhaps Wilton can hardwire a timer or a sensor that switches off when fully charged. It seems that 15-20 minutes would not be enough time to fully charge a low battery. He and I have exactly the same purpose in mind: powering an auxiliary item for an indefinite period of time yet retaining all the other features of the system. I'm absolutely convinced (leap of faith) that all that is required to disable the timer function of the high-current relay (and it's not part of the switch) is a blob of solder in the right place. But getting to it, and finding out where to put the blob, may well be beyond Wilton's abilities at this point. We have no 124, so I can't even try to look into it for him. -- Jim
Re: [MBZ] 124 rear defroster timer
On Wednesday, February 15, 2006, at 02:49 PM, Jim Cathey wrote: He and I have exactly the same purpose in mind: powering an auxiliary item for an indefinite period of time yet retaining all the other features of the system. I'm absolutely convinced (leap of faith) that all that is required to disable the timer function of the high-current relay (and it's not part of the switch) is a blob of solder in the right place. But getting to it, and finding out where to put the blob, may well be beyond Wilton's abilities at this point. We have no 124, so I can't even try to look into it for him. -- Jim Is it the challenge of getting it to multi-task? I know by now I could have run a new wire back off of some sort of relay that opens the circuit when the key gets turned off. Discrete too. Maybe I'm missing something about the whole picture? Johnny B. I Mac Therefore I am
Re: [MBZ] 124 rear defroster timer
On Wednesday, February 15, 2006, at 04:46 PM, wilton strickland wrote: Johnny, part you may be missing is that I'm no longer physically able to do most things that to most of us are very easy. 46 yrs ago, I could dismantle and reassemble a jet engine. 'Til coupla yrs ago, I had never seen anything that I thought I could not do. If my hands didn't shake so, I'd have run appropriate charging circuit with switch to trunk several wks ago. 'Realized coupla days ago that an appropriate circuit, with switch, that I never use (defrost) terminates only a few inches above trunk where I need it. 'Even considered rear vanity/dome light circuit, but 'fraid it may not handle charger. Wilton I understand your inability to do many things but it seems you will need to modify the system which may take more effort than running a new wire. I see how the wiring for the defrost is convenient. Johnny B. I Mac Therefore I am
[MBZ] 124 rear defroster timer
Where is the 20-minute timer for rear window defroster on my '87 300D? Wilton
