schematic for rear defroster-1989?
12-26-2010, 09:11 PM
#18
Team Owner
that's obviously a single layer board Doyle you should be able to draw that out pretty quick as long as that transisitor follows standard BCE format for the transistor .. but ya never know with these Germans ..
12-26-2010, 09:39 PM
#21
Rennlist Member
Thread Starter
Just to post from PP from a great fellow who's participating within this issue..
His post will be attached (edited, for just the post from HELLA)
Thanks everyone!
Doyle
His post will be attached (edited, for just the post from HELLA)
Thanks everyone!
Doyle
12-26-2010, 09:49 PM
#22
Rennlist Member
Thread Starter
I'm thinking of the following (and I'm no mechanic):
My big boat anchor Porsche battery has been in there well past 7 years......it's really time to replace. I've been tracking the voltage each morning (precrank), via thew radar detector readout from the cig connection (it's within 1/10 DCV from the battery measurement0....I've noticed some voltages that don't reflect 100% charge so time draws near...as to DRIVING,..the voltage readout is fine (within specs),..with the VR doing it's job based on what it needs to do........can be temp dependent,..can be time dependent (2 days-down,..vs. 5 days down)....she's fine.......SO:
In all cases, the cirscuit #2 requirement for it's "triggered" DC level is NOT an issue within my car. She'll (easily) see +13.0 VDC at all times,..at ALL stages....SO,..the input data is good to go. I suspect the integral circuitry would be engineered to accomodate the noted contention of various level trip points...can't wait to get this sketched out!
One thing's FOR SURE: this old (original) electrolytic cap will be changed (on principle, as they don't get better with age),..with a lofty voltage rating on the new one.
Patience is NOT a virtue.
Doyle
My big boat anchor Porsche battery has been in there well past 7 years......it's really time to replace. I've been tracking the voltage each morning (precrank), via thew radar detector readout from the cig connection (it's within 1/10 DCV from the battery measurement0....I've noticed some voltages that don't reflect 100% charge so time draws near...as to DRIVING,..the voltage readout is fine (within specs),..with the VR doing it's job based on what it needs to do........can be temp dependent,..can be time dependent (2 days-down,..vs. 5 days down)....she's fine.......SO:
In all cases, the cirscuit #2 requirement for it's "triggered" DC level is NOT an issue within my car. She'll (easily) see +13.0 VDC at all times,..at ALL stages....SO,..the input data is good to go. I suspect the integral circuitry would be engineered to accomodate the noted contention of various level trip points...can't wait to get this sketched out!
One thing's FOR SURE: this old (original) electrolytic cap will be changed (on principle, as they don't get better with age),..with a lofty voltage rating on the new one.
Patience is NOT a virtue.
Doyle
12-26-2010, 09:56 PM
#23
Rennlist Member
Thread Starter
Before frostbite set in,..I did check component values of all resistors, diodes,..cap showed charging but quite slow......she's almost 22 years old,..whatdoyaexpectfromaelectrolytic? All checked within tolerances. (cap will go.
I do have transistor testers, curve tracers, etc. within my shop but was overcome with coldness to make sense of efficiencies....could have easily checked those transistors out,..even by the nice fire tonight....MAN,..I HATE COLD!!!!!!!
AGAIN,..I'll get to the MANUAL closing of relay #2 and see if she delivers the goods across her contacts,..if the contacts prove interfering, I'll simply jumper the contact points and look for epiphany.......easy to diag a frikin coil/relay ***'y,....(YAWN]..........
Soon,...so soon.
Best to all,...
Doyle
I do have transistor testers, curve tracers, etc. within my shop but was overcome with coldness to make sense of efficiencies....could have easily checked those transistors out,..even by the nice fire tonight....MAN,..I HATE COLD!!!!!!!
AGAIN,..I'll get to the MANUAL closing of relay #2 and see if she delivers the goods across her contacts,..if the contacts prove interfering, I'll simply jumper the contact points and look for epiphany.......easy to diag a frikin coil/relay ***'y,....(YAWN]..........
Soon,...so soon.
Best to all,...
Doyle
Ed,
Got the email. I appreciate the effort,..this was a factory rendition
In any case,..still not what I'm after....you will notice on attachment #1 (that shows the relay box in question) sshows ONLY a single transistor symbol,..and NO other components,..that is, it's a block diagram, .....I'm looking for the circuit,...i.e., how the following is laid out "electronically ,..that is,..a schematic.....
I'm still looking for this print,.........(argh)
Thanks again, Ed.
Doyle
Got the email. I appreciate the effort,..this was a factory rendition
In any case,..still not what I'm after....you will notice on attachment #1 (that shows the relay box in question) sshows ONLY a single transistor symbol,..and NO other components,..that is, it's a block diagram, .....I'm looking for the circuit,...i.e., how the following is laid out "electronically ,..that is,..a schematic.....
I'm still looking for this print,.........(argh)
Thanks again, Ed.
Doyle
12-26-2010, 10:19 PM
#24
Rennlist Member
Thread Starter
Sharing a bud's post from PP: Just more data,.....
http://forums.pelicanparts.com/porsc...es-unplug.html
Best,
Doyle
http://forums.pelicanparts.com/porsc...es-unplug.html
Best,
Doyle
12-26-2010, 10:29 PM
#25
Rennlist Member
Thread Starter
I'm thinking FIRE ALL OF THE ELEMENTS UP AT FIRST then one would decrease voltage on selected (outer) elements..? When done, cut the damned switch off....
We'll get to the bottom of this..
Doyle
We'll get to the bottom of this..
Doyle
12-27-2010, 01:34 AM
#27
Doyle,
When you get the Txistor P/Ns, send them to:
xref@onsemi.com
They will get you a cross to the current devices and then you can buy them at Digikey or Avnet express.
When you get the Txistor P/Ns, send them to:
xref@onsemi.com
They will get you a cross to the current devices and then you can buy them at Digikey or Avnet express.
12-27-2010, 12:15 PM
#28
Rennlist Member
Thread Starter
Yes, they are, Bird.
Through a 25 amper fuse to the actual switch.....This will, in turn, provide a straight DC voltage path (through it's contacts), to the sideview mirrors. One VERY important footnote (970-55/Bentley) is that the pwr mirror switch gets its ground from a tap off at the left outside mirror!!!!. In no cases are transistors used !!!!!!!!!!!!
On with the defog circuitry......(with transistors).......
Best to you and yours' Bird!
Doyle
12-27-2010, 12:17 PM
#29
Rennlist Member
Thread Starter
Doyle,
When you get the Txistor P/Ns, send them to:
xref@onsemi.com
They will get you a cross to the current devices and then you can buy them at Digikey or Avnet express.
When you get the Txistor P/Ns, send them to:
xref@onsemi.com
They will get you a cross to the current devices and then you can buy them at Digikey or Avnet express.
Best,
Doyle
12-27-2010, 12:49 PM
#30
Rennlist Member
Thread Starter
Gerry,..being off today, I couldn't resist....
As to that email you posted, might I ask a few questions? Tobetter clarify his offerings?
"the first stage (center elements) of the heating is operational at 10.5 VDC",..I ask "measured where"?
the second stage )upper/lower elements) is working at 12.8 VDC......I ask, "measured where"?
In BOTH cases, my system voltage is well above that....I think this to be irrelevant, as the circuitry is controlling the "ratios"... and we WON'T know, until we've the schematic on the circuit!!!!!!!!
FUN!!!!!
Doyle
As to that email you posted, might I ask a few questions? Tobetter clarify his offerings?
"the first stage (center elements) of the heating is operational at 10.5 VDC",..I ask "measured where"?
the second stage )upper/lower elements) is working at 12.8 VDC......I ask, "measured where"?
In BOTH cases, my system voltage is well above that....I think this to be irrelevant, as the circuitry is controlling the "ratios"... and we WON'T know, until we've the schematic on the circuit!!!!!!!!
FUN!!!!!
Doyle