electrical and ignition Electrical Issue

[Mq2002]

hello all,

I am looking for suggestions.  I am an amateur mechanic in need of some advice. I have a 1973 2002tii that will not start.  I drove it last a couple of weeks ago after it sat out in a rain storm.  The car started fine and I put it in the garage.  When I went out to start it last weekend, it would not turn over.  I could not hear the fuel pump go on.  In fact, there does not appear to be any power to the car at all.  All connections and fuses appear ok.  I took the battery in to have it tested and it appears to be fine.  (The guy at the store looked disappointed- he wanted to sell a battery).  The ground is secure.  There is no power to the car period.  Any help is appreciated.  Thanks, Marc

[M3M3M3]

start simple.  trace power from battery to starter and to fuse box.  check for 12v all along the path until you find where things are disconnected.    i am guessing it is the wire between battery and fuse box.  is EVERYTHING dead, or just the things that come on with key on?  that helps narrow it down also.  if just keyed stuff, could be ignition switch connection.

 

i am sure it is a simple loose wire somewhere...start following the path from the battery.

[Mq2002]

Everything is dead!

[Mq2002]

Everything is dead!

[ptbadboy]

Have a '75 Inka square light.

 

I've dealt with lots of electric issues myself this past couple weeks in the ignition switch system. Do you have a DMM? Great tool, well worth the cost. This will confirm continuity in your system, as well as voltage. For continuity, must have battery disconnected !

 

Somehow the PO, after extensive sound system and extra gauges added,  got the ignition system to work through a relay under the dash that was attached to the steering column just before the ignition switch saddle. The starter wire went through this relay. After having been able to jump the starter with a remote starter switch(auto parts store), with the key on, it started every time. Turning the key itself wouldn't start it.

After much study, and lots of un-neccessary parts replacements, including the ignition switch and the relay, I realized wiring diagram showed this relay as used only for automatic tranny system, in conjunction with a ghost detent reverse cutout switch somewhere downline. Using the DMM continuity function, I determined that the ground wire out of the relay that went to this ghost cutout switch didn't complete it's circuit. Don't know if this was an automatic at one time, or if the factory installed this system standard to accommodate that option down the assembly line. Absolutely everything in the system checked out, including the old relay, which I had replaced before finding out how to test them. It wasn't until after I had replaced the ignition switch(expensive, and a PITA to replace), and it still didn't start, that I realized I could just bypass the relay.

Voila!! Holy s---t. Starts all the time with the key!!

 

I did complete suspension bushings renewal, as well as all front end steering and ball joints. I also did lots of work beneath the dash when rebuilding the heater box. And somewhere I must have disconnected  or cut the ground wire to the ghost detent switch. Soon, I will spend some time tracing that ground wire to find the ghost switch, but it's not needed in my 5speed setup, so for now, screw it,  I'll drive and smile.

 

Back end of this story is that I have an extra ignition switch, with keys, that works just fine.

 

I also have a story to relate about how to avoid rekeying your door handles to new ignition switch(of course again after un-neccessarily having spent the money precisely to do that).

 

Swap the key cylinders in the ignition switch. But I won't relate the experience here at this time. Unless you do find it's the switch. Then you can write me and I'll send you pics of what to do, and not to do. I will post photos in the near future of all this for others that may be able to use them. But too exhausted right now, and need wind in my hair for a while. Know what I mean?

 

don

510-528-1390

donsweetpeaATcomcastDOTnet

Edited June 1, 2013 by ptbadboy

[c.d.iesel]

battery cable ends - BOTH ends of the cable - condition ?

 

battery ground cable - same - condition at both ends? Clean and tight ?

 

ground cable from motor block to inner fender - same as above - condition?

IS THERE A GROUND CABLE BETWEEN THE BLOCK AND INNER FENDER/BODY?

SHOULD BE ONE -

[Napes]

ptbadboy:  The ground wire you discovered quite probably originally went to the Neutral Safety Switch on the automatic transmission.  It's a switch that prevents the car from being started except when the auto tranny is in Park or Neutral. The switch, when the auto tranny is in place, is located in the lower, forward, left-hand side of the auto tranny.  Obviously, with the 5-speed, you no longer need the switch (which, incidently, is a real PITA to change-out).

 

Bob Napier

Edited June 1, 2013 by Napes

[ptbadboy]

ptbadboy:  The ground wire you discovered quite probably originally went to the Neutral Safety Switch on the automatic transmission.  It's a switch that prevents the car from being started except when the auto tranny is in Park or Neutral. The switch, when the auto tranny is in place, is located in the lower, forward, left-hand side of the auto tranny.  Obviously, with the 5-speed, you no longer need the switch (which, incidently, is a real PITA to change-out).

 

Bob Napier

Thanks Bob. Sounds like you're back on the road to soundness. Good to hear from you.

 

But the fact that the switch was wired through the relay that is used for auto tranny,  and obviously worked before I fooled around under the car and under the dash, leads me to believe that either the car had an auto tranny at one time, or as I said, the factory installs the relay/neutral safety switch circuit for easy optional auto tranny install further down the line.

But that still doesn't explain how the PO got it to work through the optional relay, unless the ground worked.

 

When I bypassed the relay, I merely disconnected the female on the EXIT side of the relay that went to the starter, and plugged it onto terminal 50 on the ignition switch where the starter wire TO the relay was formerly connected.

 

Would be interesting if someone else with stock 4 speed were to look under dash to see if there is a relay wired into the starter circuit between the ignition switch and starter. How about yours?

 

don

Edited June 2, 2013 by ptbadboy

[bcarey]

I had a similar problem a few weeks back. Battery had plenty of juice, but nothing would happen when I turned the key. Nada. Grounds were good, but the connection to the starter motor was loose and kind of mucked up. I took a wire brush and some of that fancy electrical sprays stuff to it, reconnected everything and PRESTO! Car turned over on my second try. Has been running smoothly (or as smooth as it ever runs) ever since.

[sczapiga]

I just found this relay you speak of on my 75’ 4 speed 02’. Did an oil change and removed the battery to aid in access then after hooking it up… nothing. Starter did nothing when turned key. We traced the starter wire to that same relay under the dash to find we could jump it and it didn’t seem to mess anything up. The schematic shows it’s the auto safety switch like you said which made me think maybe my car was auto in another life? Who knows, 

 

does anyone know if we actually need the relay? Can I just straight wire the starter wire to the ignition switch? 
 

thanks!

[AustrianVespaGuy]

So yes, i believe that diagram is mislabeled, as i think this starting today is in all manual models too. It also never made much sense to me, as it doesn't really DO anything in the manual as one side of the coil is just grounded instead of going to the shifter interlock; it's just an useless interrupt to the starting circuit. But no, you don't need it, just run the black/white wire straight to the solenoid and avoid this unnecessary extra point of failure.

Edited September 11, 2021 by AustrianVespaGuy