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1st off i did search search and search i bought a t2 that was sitting for 14 years owner say the engine blew up. i tow the car my house and start working in it. i got it running by hot wiring the starter and poring gas thru the intake. if i tried with key all the accessories works but no dummy lights on and no crank. i replace the ignition switch but stillthe same issue , i tried a spare ecu and nada, i also check fuses and most of the relays. Also did a compression test 120 both rotors. 1987 turbo II
There are two switches on the clutch pedal. The one higher up is the interlock switch. It has two wires, one being Black/Green and the other is Black/Red. W/key to start the B/G wire should have voltage. If it doesn't then you could have an issue w/the starter cut relay. At this relay the Blue/Black wire would have voltage w/key to start. If it does not then there is an issue w/the ignition switch. If there is voltage on this wire as stated then the next thing to check is w/key to start if the thicker Black/Green wire has voltage or not. This B/G wire is the same as the B/G wire in the interlock switch thus you could check the wire there (starter relay) instead of climbing under the dash to check the wire at the top of the clutch pedal.
Somewhat incorrect satch. The top switch for the clutch is for cruise control and the bottom switch on the firewall is the interlock (and it's a bitch to get to!).
Where's the battery? And did you try what I suggested? Also, the ECU has nothing to do w/your problem as you have a problem w/the starting circuit which includes the ignition switch, starter relay, interlock switch and the starter. Checking the wires will isolate the problem which is what you need while just replacing parts just tells us you replaced parts. Make sense?
For some reason of my own I thought you had an S5 when you have an S4 (and I apologize for that). With that said, the interlock is fed power via the B/R wire. With the clutch depressed and key to start the voltage from the B/R wire passes on to the B/G wire in the switch thus the thick B/G wire in your pic (the one w/the jumper) should then have voltage w/key to start and clutch depressed. If it does not then the problem is at the interlock. Again, the colors of the two interlock wires are B/G and B/R. If you see a wire w/Yellow to it then that is the clutch switch and not the interlock.
this is what mine has and is a biach to get too lol i dont even see any wires going to it
Originally Posted by satch
For some reason of my own I thought you had an S5 when you have an S4 (and I apologize for that). With that said, the interlock is fed power via the B/R wire. With the clutch depressed and key to start the voltage from the B/R wire passes on to the B/G wire in the switch thus the thick B/G wire in your pic (the one w/the jumper) should then have voltage w/key to start and clutch depressed. If it does not then the problem is at the interlock. Again, the colors of the two interlock wires are B/G and B/R. If you see a wire w/Yellow to it then that is the clutch switch and not the interlock.
this is what mine has and is a biach to get too lol i dont even see any wires going to it
Again, the B/R wire from the ignition goes to the interlock. If the interlock worked correctly it would pass the voltage to the B/G wire. You do not have to check the B/G wire at the switch because it is the same wire found in the plug which is jumpered (on a side note, the B/G wire and B/W wire in that plug comes jumpered from the factory. If yours was not then that represents one problem). So if you don't want to check the B/G wire at the interlock then you don't have to for it's easy peasy, just check it at the plug w/the jumper. Understand. If the B/G wire in question does not have voltage w/key to start and the clutch pedal depressed then the interlock is not working, or the plug to the interlock is not plugged in or the B/R wire feeding voltage to it has no voltage w/key to start which is unlikely since I think you already checked that wire.
As far as the interlock is concerned, it does the same thing as the stop light switch for it senses whether the pedal is depressed or not. To do this the switch must rest against the clutch pedal to do so. The switch has a little plastic button which is spring loaded and only registers two positions, either the pedal is depressed or it is not. When the pedal is not depressed the button recedes into the switch and there is no continuity between the two wires to the switch, while if the pedal is stepped on then the pedal pulls away from the switch and the button protrudes from its housing and there is continuity which allows any voltage on the B/R wire to pass to the B/G wire. Thus it appears you are highlighting the wrong item. Look towards the top of the pic and notice the item resting against the pedal armature. If it has a pigtail running to a plug w/the B/G and B/R wires then that's the interlock. Okay?
I had a similar problem when I did an engine swap in my car recently. Is the small black x23 connector under the fuse box in the engine bay connected? I left it unconnected on accident and my starter, turn signals, and wipers would not work but most of the rest of the car did.
If that's not it, Satch is the master at figuring out electrical issues in these cars.
Last edited by Lavitzlegend; Aug 28, 2015 at 03:06 PM.
Again, the B/R wire from the ignition goes to the interlock. If the interlock worked correctly it would pass the voltage to the B/G wire. You do not have to check the B/G wire at the switch because it is the same wire found in the plug which is jumpered (on a side note, the B/G wire and B/W wire in that plug comes jumpered from the factory. If yours was not then that represents one problem). So if you don't want to check the B/G wire at the interlock then you don't have to for it's easy peasy, just check it at the plug w/the jumper. Understand. If the B/G wire in question does not have voltage w/key to start and the clutch pedal depressed then the interlock is not working, or the plug to the interlock is not plugged in or the B/R wire feeding voltage to it has no voltage w/key to start which is unlikely since I think you already checked that wire.
As far as the interlock is concerned, it does the same thing as the stop light switch for it senses whether the pedal is depressed or not. To do this the switch must rest against the clutch pedal to do so. The switch has a little plastic button which is spring loaded and only registers two positions, either the pedal is depressed or it is not. When the pedal is not depressed the button recedes into the switch and there is no continuity between the two wires to the switch, while if the pedal is stepped on then the pedal pulls away from the switch and the button protrudes from its housing and there is continuity which allows any voltage on the B/R wire to pass to the B/G wire. Thus it appears you are highlighting the wrong item. Look towards the top of the pic and notice the item resting against the pedal armature. If it has a pigtail running to a plug w/the B/G and B/R wires then that's the interlock. Okay?
Unless the S4 is backwards satch, the switch highlighted in post #12 is the starter interlock switch. The one you are referring to is the cruise control kill switch so the engine doesn't explode.
Unless the S4 is backwards satch, the switch highlighted in post #12 is the starter interlock switch. The one you are referring to is the cruise control kill switch so the engine doesn't explode.
(Yes, I know he doesn't have cruise control)
I should have relied on the link provided to differentiate the two from a physical aspect as opposed to relying on the wiring diagrams (my favorite). Using the diagrams tells me what wires run to the item thus if a person is looking at the switch and they are not sure of its position then the wire colors helps to identify the proper part. I have an auto thus no clutch, interlock crap. Thanks for helping to pull my head out again (I think).
Good. Something so small but yet a pain in the rear, like that ever happens.
previous owner rebuild the engine and told me car didnt start after a day of the rebuild , he thought engine was bad , the car sat outside for 14 years. now its alive thanks for your help !!! , im going to replace all rubber parts and all the fluids
thanks yall , it was a biach but i was able to bypass the interlock switch , no space there at all .
