93'escort 1.9L no power getting to starter

[cclouser88]

I have a 1.9L escort automatic I changed the battery,the starter,the relay,the ignition switch,and the tumbler but the starter still won't turn over.If I strait line it to the battery it'll start the car but can't toggle switch it cause the fan and other componants run off starter ground I'm tired of spending money on "not the problem" is there some way to check the nuetral safety switch?If so how? please help me with this ongoing battle. Thanks in advance

[tripletdaddy]

I'm not sure I understand what you mean by "can't toggle switch it cause the fan and other componants run off starter ground." Do you mean you can't or don't want to put a srewdriver across the starter studs to jumper the starter from the battery line?

You said you replaced the relay. Whether it is on or separate from the starter, touch a jumper wire from the battery + to the ignition switch terminal with the ignition wire removed. That should turn the starter. Next, hook up the voltmeter positive lead to the removed ig sw wire and ground meter while turning the key to start. If nothing, than, since you have eliminated everything else, than either your nuetral safety switch,nss, is bad or the shifter and it are misaligned. Will it start if slightly off of park or nuetral? If you can not get it to start in any position of the shifter, than you probably have a bad nss,trs,dtrs. The switch is found on top of the transmission with the shifter cable/linkage attached to it. Remove the electrical connector to it. Have someone put the key in start and you test for 12 volts on both pins. If no voltage, than it's not getting from the ign sw to nss. If good, then do a continuity test of the nss across the two connector pins. You can also perform this test by reconnecting the wires to the nss and check for 12 volts on the second wire by sticking your probe or pin in the back of the connector at the wire, while in park neutral, etc to see if you can get voltage in any position. You may want to disconnect the coil wire for that. If that's good, then you need to check for continuity from the nss to the relay.

Chances are, you are probably right that your nss is the culprit as you have virtually replaced everything else. The wiring and connectors are all that remain. And even they could develop something not particularly visible like a break or corrosion. Let's hope for something straightforward.

[cclouser88]

thank for the info this problem started about 2 months ago i can here a clicking in the relay (upper passenger side along firewall) so I started with that when that didn't help I changed the tumbler and ign switch once again it wasn't the prob. so I got fustrated and just sent a line from battery to starter small or s connection on the solenoid with a toggle switch to start the car.It worked so I'd just been doing that but now that it's getting warmer out my fan wasn't kicking on.It relys on the s connection on the starter. idk how or why but I had to reconnect it to get power to the fan. so now i cant toggle my starter. I checked the s wire and theres constant power going through it when key is turned on but no extra when key is turned to the start position. I still hear a clicking in the relay when i try to start it. it starts sometimes and dont others idk?. My wife over heated it back in Jan. the thermostate failed and it blew the head gasket so i had replaced those and it ran good for about a month or so then this started. I tried to start it in all gear and even between them and still get nothing. i'll check for power at the nss but theres 3 sets of wires going in or out of it with 5 to 6 wires each set (automatic trans) trying to find a diagram of system. thanks again and anything else let me know.

[tripletdaddy]

This is getting complicated.
-I was able to find at the Autozone.com site some wiring diagrams, but they aren't the clearest unfortunately to help me understand the relationship between the start switch wire and your fans.
-what do you mean when you go from run to start with key, there is no "extra" power? Either you have or don't have 12v.
-Since you said you have several wires going to the transmission switch, Transmission Range Selector, or over glorified Neutral Safety Switch,nss, (aka manual lever position switch). The starter circuit wires are Black/DarkBlue to the NSS in from ign sw(but changes to black/yellow at switch) , and Black/Red out to starter. I'd be very careful around those wires not shorting any or you will cook the computer. .
-I think I figured out the wiring circuit, as what I needed was not in one place. If I'm clear, sometimes you can get everything to work, start, fans with it all hooked up correctly? Sounds like a bad connection, wire, ground still. I can't decide if you may have a bad relay gone crazy that is connected to the engine fuse and controls the power to the rad fan circuit. It Though that doesn't very well explain the no start. Hmph, you can start it with the jumper but not with key? That ruins the idea that it HAS to be the engine is not grounded good enough. Darn!
-Anyway, you should be able to reconnect the ignition switch wire at the starter solenoid and continue to use the toggle start wire to start it. As you know, all you are doing is replacing the nss, key switch and their wires with a new one with a toggle sw, so it should work safely like what is original. Did you remove the ign sw wire from the key so you didn't back feed power? I would if you could.

- After lengthy consideration of everything, your nss is my best guess for the problem, assuming I understand your symptoms. It's a little confusing and the way the circuit was constructed including the fan power relay in the start circuit just doesn't make any sense to me. BTW, the fan relay is in your power distribution box under hood. Is that what you heard clicking and not the starter solenoid? Good luck.

[Selectron]

Just a few words on the relationship between the starter solenoid 'S' terminal and the Fan Power Relay coil, which may help to clarify things a little.

If you look at Fig.2 below (these diagrams are for the '95 1.9L but I believe your '93 is identical), you can see that the Fan Power Relay coil is grounded via the starter solenoid 'S' terminal and then via the starter motor 'Hold' winding. Note that (as I've indicated on the diagram) that isn't a true ground, but rather it's a virtual ground - the resistance of the Hold winding will cause it to sit slightly above ground potential at all times. I reckon the reason why they will have done that is this: during normal running, the virtual ground point is very close to 0V and therefore the Fan Power Relay coil will be energised (the switched contacts within the relay will therefore be closed and current will be available, as required, for fan operation). However, during cranking the top of the Hold winding will rise to 12V (supplied via the ignition switch 'Start' contacts), and that achieves two things - firstly, it holds the starter pinion in the meshed position with the flywheel to allow engine cranking, but also the low end of the Fan Power Relay coil will now be at 12V - this causes the relay to switch off - therefore the cooling fans are temporarily disabled during cranking - this maximises the current available for cranking, which is always a good thing eh, so I reckon that's why they configured it that way. (If it isn't immediately obvious that the relay will switch off during cranking, then consider that you have 12V at the hot end of the relay coil but now also 12V at the low end of the coil - that means there is 0V potential difference across the relay coil, and hence it will not be energised).

So having established that, it follows that when the starter is operated under normal conditions, via the ignition switch 'Start' contacts, then the Fan Power Relay will click off at the same instant that the starter solenoid engages - this will likely explain the relay click that you hear (there is no starter relay by the way - just the solenoid mounted on the starter motor body).

As for measuring 12V on the starter solenoid 'S' terminal with the ignition in the 'Run' position as well as in the 'Start' position, well you should only get a 12V reading in the 'Start' position - unless the 'S' terminal is disconnected at that time, in which case you will indeed read 12V whilst in the 'Run' position - but that 12V will be arriving via the Fan Power Relay coil. Upon reconnecting the 'S' terminal though, the relay coil will once again be grounded and that 12V reading should vanish when the ignition switch is in the 'Run' position.

I suspect that the 'S' terminal was indeed disconnected when you got that 12V reading in the 'Run' position, but if not then let us know because that would be very significant.

If that's the case, then it looks like you'll just have to trace the 12V along the path from ignition switch Start contacts, to Transmission Range Sensor/Switch, to solenoid 'S' terminal (see Fig.1 below). I hope that clarifies things a little, and let me know if you don't follow any of it. Oh yes, and notice that tripletdaddy made reference to the wire colours changing as they enter the Transmission switch - that detail isn't shown on my diagram.

Starter circuit - Fig.1
Starter circuit - Fig.2

[tripletdaddy]

Thanks Selectron for that excellent explaination of the grounding of the fan power relay through the starter assembly. I looked at that circuit to try and figure out why what was going on with the fan not working unless connected to the s terminal on the starter. Had me stumped at first until I saw the schematic. Then I realized, oh? They did it that way? Strange. One of the things that bothered me was why didn't the power to the fan relay coil that went through the starter for ground wouldn't enrgize the starter any. I then decided the resistor in parallel with the coil must drop the voltage enough to prevent that from happening. Right? This circuit design reminds me of a backfed ground for a taillight that has a failed ground, commonly found on trailers, where the light bulb circuit cannot get ground correctly and gets it backfed through another bulb filament to its ground. Classically can be seen on a trailer whose signal lights will alternate with the running lights, getting their ground through the running lights or the other signal light.

CClouser88, clarification does need to be made on under what conditions you measured power at S, because what was described was not consistent with the wiring diagram and made it harder for me to understand how your problem made sense with the circuits as the information seemed conflicted. As Selectron said, were your measurements made with the wires removed from the S terminal for both start and run? And were you testing the end of the disconnected wires or at the starter solenoid terminal, (which should give you nothing), or with all the wires connected to the starter?

Selectron, oh, BTW, the wiring colors are on your diagrams, but the lettering is so tiny it can't be easily read. I have the exact FSM diagrams. Do you know you can zoom in on the diagrams so you read the illegible lettering? Give me a PM if you have any questions.

[Selectron]

Originally Posted by tripletdaddy

... One of the things that bothered me was why didn't the power to the fan relay coil that went through the starter for ground wouldn't enrgize the starter any....

That's a good point, and a valid one. The answer is straightforward enough but it will require a few paragraphs and a diagram or two to explain fully so I'll start a new thread later where we can look at it in greater detail - it's more detail than this thread requires so it would effectively be off-topic. Very good point though, and I'll try to return to it this evening.

[cclouser88]

Thank you both for your insight on this crazy (to me) wireing problem. I did have the s terminal disconnected when I checked it. so the reading I was getting was from the fan relay? I checked and have voltage going to the nss and it increases when I turn the key from "run" to "start". So I know im good up to that point. I'll be checking for continuity through the nss today as long as the rain holds off.This should tell me if it's good,right? Thanks for the diagrams Selectron and the zoom tip tripletdaddy. Electric is not a strong point for me so this has all been a learning exp.and I'll let you know my findings. thanks again.

[cclouser88]

I checked for continuity through my nss and got none.

[Selectron]

Yes, with the S terminal disconnected the wire will show a reading of 12V, but that's arriving from the fan relay coil. That's entirely normal and has no relevance to your starter problem, so just forget about that and keep your attention instead on the path from ignition switch Start contacts to transmission safety switch to solenoid S terminal.

I'm not sure why you would have voltage at the safety switch in the Run position which then increases in the Start position - I'd have been expecting OV in Run position, increasing to 12V in Start position, but given that you've said you don't have continuity through the safety switch it doesn't really seem worth pursuing right now.

The bottom line is that you should have had continuity through the switch, and if the ignition was switched off at the time (because you can't check for continuity on a live circuit) and if you were definitely checking the correct pair of wires (with the meter set to the resistance range, of course) but still didn't have continuity in the Park or Neutral positions, then the switch must be faulty. If it's the original switch still in there since '93 then that wouldn't be too surprising eh.

[tripletdaddy]

cclouser88, just to be sure your nss is bad, I would recommend one last electrical test of your nss that would confirm your no continuity measurement. Measure 12volts on BOTH sides of the switch, with the downstream side disconnected. This would be the side that goes to the starter and the other being from the ignition switch. Obvioulsy, with key in start and N or P gear.

[tripletdaddy]

cclouser88, have you fixed it? or is it still unsolved? Let us know how you fixed it or your latest finding. Thanks

[cclouser88]

I checked the switch again and got no reading (the 12V test) I'm going to replace the switch this weekend coming up. I'll definately let you guys know what happens and I appreciate all the time and help.

[ogrethemage]

Originally Posted by Selectron

.......So having established that, it follows that when the starter is operated under normal conditions, via the ignition switch 'Start' contacts, then the Fan Power Relay will click off at the same instant that the starter solenoid engages - this will likely explain the relay click that you hear (there is no starter relay by the way - just the solenoid mounted on the starter motor body).

There are relays up in the upper passenger side firewall, the one closest to the fender well is identified by various sources as the ignition relay and is probably what you hear clicking, the other is the fuel pump relay.

I have same issue, I try to start and all I hear is 2 clicks from the relay....but no starting of the vehicle.