Guest waydizzle Posted August 27, 2017 Share Posted August 27, 2017 I'm having some weird power problem with my ACC power...again. About a year ago I was having this issue and thought it was a "reverse" turbo timer so I completely removed the turbo timer and reconnected all the original harnesses. Problem went away for about a year and now it's back. Long story short, my radio, clock, cig, pretty much all ACC gets power on it's own after engine shut down for ~5 to 10 min (without key in ignition). The weird thing is, whenever I press the cig light, it will cut the power out immediately. Sometimes it will cut out for a day...most of the time will only cut out the power for minutes until it comes back on again. I did noticed that the ABS? box (underneath my dash there's a long box with 3 orange connector and a small box sitting on top of it with a gray connector) had clicking noise whenever it turns on/off. So I completely disconnected that thought it was some kind of relay inside being bad but it didn't help. I thought it might've been my ignition SW soo i disconnected that too and power still comes on. I also noticed my Slip Con light is now constantly on where as before it was off and sometimes intermittently come on but always go out Can any guru out there please give me a good direction to go about troubleshooting this... because at this point I have no idea where I can look into. honestly any help is greatly appreciated at this moment. car is a 93JDM TT Quote Link to comment Share on other sites More sharing options...
ibby Posted August 27, 2017 Share Posted August 27, 2017 Check your relays. Thars the ticking noise. Check earth's Quote Link to comment Share on other sites More sharing options...
Guest waydizzle Posted August 28, 2017 Share Posted August 28, 2017 I unplugged all the relays under the driver side kick panel and still no luck... and i do not see any relay underneath the center dash console where the noise was coming from. the noise was coming from this box but when i completely disconnect that box.. problem still there Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted August 28, 2017 Share Posted August 28, 2017 It's not got one of those huge capacitors for a large stereo install in the boot has it? Big caps "charge themselves up again" when discharged. If it still has the electric aerial, is it doing odd things and not retracting properly? Quote Link to comment Share on other sites More sharing options...
Hitbox Junkie Posted August 28, 2017 Share Posted August 28, 2017 Sounds like a cap slowly discharging. And when pressing the cig lighter your dumping the charge. Don't know how to fix it mind. Quote Link to comment Share on other sites More sharing options...
jagman Posted August 28, 2017 Share Posted August 28, 2017 As you have disconnected the ignition switch - and problem still exists , you are looking at a power feed from a chaffed wire , contact between power circuits . There are about 6 or 7 permanently live fuses , you need to pull one at a time and see which circuit is powering the ACC circuit , then use a meter on that feed to find the problem . If none of the live fuses are powering the ACC, then it's a battery feed ,and probably wrongly wired by owner -car alarm or such Quote Link to comment Share on other sites More sharing options...
Guest waydizzle Posted August 28, 2017 Share Posted August 28, 2017 As you have disconnected the ignition switch - and problem still exists , you are looking at a power feed from a chaffed wire , contact between power circuits . There are about 6 or 7 permanently live fuses , you need to pull one at a time and see which circuit is powering the ACC circuit , then use a meter on that feed to find the problem . If none of the live fuses are powering the ACC, then it's a battery feed ,and probably wrongly wired by owner -car alarm or such thanks for the direction Jagman. Do you happen to know which fuses are the live ones? Quote Link to comment Share on other sites More sharing options...
Mike2JZ Posted August 28, 2017 Share Posted August 28, 2017 thanks for the direction Jagman. Do you happen to know which fuses are the live ones? Remove key from ignition. Get a multimeter reading from each fuse, and see which ones provide battery voltage. Those will be your permanent live circuits. You can test the same thing with key switched to ACC to see what circuits/fuses are getting power when key is @ acc Quote Link to comment Share on other sites More sharing options...
jagman Posted August 28, 2017 Share Posted August 28, 2017 Dome ,rad ,fog ,abs ,haz/horn, efi 1 , Trac ,am2 , alt, and a couple more , you need to look at the wiring diagrams Quote Link to comment Share on other sites More sharing options...
jagman Posted August 28, 2017 Share Posted August 28, 2017 When you press in the cig lighter , it's a big load i.e. It draws a lot of current , the cross connection , chafe or contact or wire is a high resistance and it drops off the voltage on ACC busbar . It could easily be something like an alarm fitted , as these often flash headlights (perm live) or hazards or horn (perm live),so an alarm relay can have both live and ACC on its contacts , sticking contact and boom , cross feed of power .... It's always a job to diagnose elect problems without the car in front of you and a meter to prod about with. Quote Link to comment Share on other sites More sharing options...
Guest waydizzle Posted August 28, 2017 Share Posted August 28, 2017 When you press in the cig lighter , it's a big load i.e. It draws a lot of current , the cross connection , chafe or contact or wire is a high resistance and it drops off the voltage on ACC busbar . It could easily be something like an alarm fitted , as these often flash headlights (perm live) or hazards or horn (perm live),so an alarm relay can have both live and ACC on its contacts , sticking contact and boom , cross feed of power .... It's always a job to diagnose elect problems without the car in front of you and a meter to prod about with. hey thank you so much for the input Jagman. I will check all those areas that you mentioned. I do have a keyless entry installed.. maybe ill look at some of those wiring and also go back and check the previous wiring from the old turbo timer that i took out. (it was an awful job from the previous owner) I will update once i check those area this weekend. Quote Link to comment Share on other sites More sharing options...
jagman Posted August 29, 2017 Share Posted August 29, 2017 Your ACC wire pink and blue - only feeds your cig lighter and the rad no2 (radio) , or I must say SHOULD only feed these two, both via fuses So which one most likely to have been buggered with .....I'm going with the radio and maybe an antenna feed , then again there may be a memory live feed to keep radio channels stored - there is no end of ways people bodge wiring Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted August 29, 2017 Share Posted August 29, 2017 A colleague had a car in with a boot full of audio junk. The battery went flat after two days so wanting to move it in a hurry he put the booster on it to do a fast charge. A HUGE multi Farad capacitor in the boot took exception, exploded very dramatically, at the same time as the wiring to it set alight. Seems it was permanently connected to B+. Big caps that go bang smell dreadful and make a right mess... Luckily the explosion drew attention to the smoke coming from the back of the car too. Quote Link to comment Share on other sites More sharing options...
Guest waydizzle Posted August 29, 2017 Share Posted August 29, 2017 Your ACC wire pink and blue - only feeds your cig lighter and the rad no2 (radio) , or I must say SHOULD only feed these two, both via fuses So which one most likely to have been buggered with .....I'm going with the radio and maybe an antenna feed , then again there may be a memory live feed to keep radio channels stored - there is no end of ways people bodge wiring I was doing a bit of looking over the diagram last night and while i was looking at the car... If i read it correctly, the Clock and the Cig share the same 15ohm Fuse under the driver side kick panel while the radio has it's own separate fuse in the engine bay. that's why I couldn't understand how those 3 stay on when they have nothing in common other than the junction 1 connector. Quote Link to comment Share on other sites More sharing options...
jagman Posted August 29, 2017 Share Posted August 29, 2017 Yes the acc power supplies two fuses , after the fuses, one to the stereo amp ( is it fitted ?) (another source for xfeed) , the other feeds the cjg lighter and clock (clock also twin supplies and a source of xfeed) All have a common supply ACC , but with the ignition off - its no longer there , this does not stop it becoming an earth , a common earth and the earth becoming live so it powers up -cross wiring or internal short circuits or high resistance earths cause odd problems -its a case of isolating the problem , use a meter - I cant help too much as i have no idea whats been added or altered , for example a boost guage in place of the clock , or new stereo and what did they do with the wiring But you are on a correct path at least -when you find it, you always go -DOH!!!! Quote Link to comment Share on other sites More sharing options...
Guest waydizzle Posted September 2, 2017 Share Posted September 2, 2017 Yes the acc power supplies two fuses , after the fuses, one to the stereo amp ( is it fitted ?) (another source for xfeed) , the other feeds the cjg lighter and clock (clock also twin supplies and a source of xfeed) All have a common supply ACC , but with the ignition off - its no longer there , this does not stop it becoming an earth , a common earth and the earth becoming live so it powers up -cross wiring or internal short circuits or high resistance earths cause odd problems -its a case of isolating the problem , use a meter - I cant help too much as i have no idea whats been added or altered , for example a boost guage in place of the clock , or new stereo and what did they do with the wiring But you are on a correct path at least -when you find it, you always go -DOH!!!! hey Jagman, you were helping me with the ACC power issue on one of my threads, was wondering if you can give me more assistance. anyway, so i finally got some free time today to look at the problem more. This is what I found so far. from Ignition switch, there were indeed some wires piggy back into the OEM harness. it was some wires going to the aftermarket gauges and EVC boos controller (jumper into the black/white wire) The pink/blue wire (ACC) wire did not seem to have any wires taper from it. I have disconnected everything and the problem still there... I did notice that whenever I pull the 20A rad No.1 fuse, the problem stop. my radio, clock, cig, all go out. Which didnt make sense to me...because I it should've been control by Cig 15A for clock/cig and 7.5 A for rad no.2. by disconnecting the bottom left harness inside of the driver side kick panel (white long block looking harness coming out of the CB panel) would also stop the problem immediately. at least the meter reads 0v and radio turns off. Looking at the diagram, only thing that tides rad no1 and rad no2 would be the auto antenna control relay. ( i didn't get this far before it was dark) I also followed the ACC (blue/pink) wire from ignition switch upstream... it look like it goes into the factory big bundle harness.. at this point i'm not sure how to even shoot or where to shoot to isolate the problem down. Can you give me a direction to shoot to/from? thanks man Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted September 2, 2017 Share Posted September 2, 2017 I mentioned the auto aerial earlier, try disconnecting it in the boot. Quote Link to comment Share on other sites More sharing options...
Guest waydizzle Posted September 2, 2017 Share Posted September 2, 2017 I mentioned the auto aerial earlier, try disconnecting it in the boot. auto aerial?? are you talking about the antenna motor in the trunk? Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted September 2, 2017 Share Posted September 2, 2017 auto aerial?? are you talking about the antenna motor in the trunk? Yes. Quote Link to comment Share on other sites More sharing options...
Guest waydizzle Posted September 2, 2017 Share Posted September 2, 2017 i disconnected the antenna a long time ago i think.. to keep it from coming up. do you think that has anything to do with it? hmmm i might have to look in that area tomorrow. thanks for the input ! Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted September 2, 2017 Share Posted September 2, 2017 It *MAY* have a control unit behind the dash that awaits or creates a signal to say the aerial has descended, and it *MAY* run off the ACC supply. Just an idea. Quote Link to comment Share on other sites More sharing options...
jagman Posted September 3, 2017 Share Posted September 3, 2017 Ok - we are nearly there : pulling the fuse Rad 2 - removes the problem So the cross connection is from this circuit , Rad 2 circuit feeds 3 things : 1 the head unit radio 2 the antenna relay - that controls the antenna motor 3 the stereo amplifier All 3 have both rad2 and ACC supply to them , they also all have internal transistors and circuit boards - you need to unplug each one at at time , if nothing has been messed with ( additional wiring done from previous owner ) the amplifier below the seat is favourite - it's most likely to have water in it at some time or stood on or disturbed . I don't know if your head unit is stock - if not , start here . Check the original plug and loom , someone splicing power off this is favourite .The relay is behind the centre dash/glove box area , it's not a normal relay , it's also a control unit with internal transistors - but least likely to have been touched , due to location - but you never know , some people try real hard to get it all wrong. Troubleshooting circuits , you don't actually follow wires and looms , you do it with a meter and isolate first , inspecting cables is the last thing in line . I just trying to imagine people's faces if at work ,if I did that , a 4 mile circuit on a 747 , and I said "I be finished in about 3 years " - lol "I can't find and fix the fault " is also not an option , they are not likely to say "ok , we will just scrap the aircraft then " -lol Quote Link to comment Share on other sites More sharing options...
Guest waydizzle Posted September 3, 2017 Share Posted September 3, 2017 Jagman. you are seriously a life saver bro. just got your email and i went out immediately to check those locations. god fucking damn it, it was the amplifier under my seat. I disco the middle connector, and boom....power is out. check with key and turn to acc, everything is on, key off, everything off. Does this mean that the stereo amplifier itself is fried or internally shorted?? what's the purpose of that box anyway? all my stereo still work with that box disco... so i'm a bit confused on what's the purpose of that box. is it used for the factory radio head unit? btw, are you an aircraft mechanic?? Quote Link to comment Share on other sites More sharing options...
jagman Posted September 3, 2017 Share Posted September 3, 2017 The head unit is a pre amp and having a separate power amp keeps the dash board board components smaller and cooler , and a cleaner audio path - it allows more powerful speakers - cars wiring limits to 50 watt amp Yes the underseat amplifier is internally short circuited probably moisture , new head unit would probably be the easiest thing now , modern units have moved on anyway . Being a snob , I prefer "engineer " lol Quote Link to comment Share on other sites More sharing options...
Guest waydizzle Posted September 3, 2017 Share Posted September 3, 2017 so bypassing the entire power amp wouldn't do anything at this point right? i already have an aftermarket head unit installed and everything seems to be functioning. Just for fun, I shot the wires coming out of that 6 pin connector.. i think 3 of the wires had live 12v. Which I thought was a bit weird...because from the schematic, only pin 6 and pin 2 should have power since it's coming straight from the 20A rad no.1 and pin 3 gets power when key is in ACC. Should I look more into this or just leave that connector disconnected? I'm a jet mechanic myself, avionics field more precisely. Maybe it's experience around jets... looking at aircraft schematic is a lot easier than car diagram for some reason.. hahaha. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.