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Discussion Starter #1
My 95SS has the Z28 cluster mod, so no Passkey/Vats warning light. I went to get gas last night and car wouldn't start back up. Towed it home and did the following checks:

1. plenty of battery and good charge.
2. when starter switch is turned on, you can hear the fuel pump whine nicely, but no starter at all.
3. no voltage at the yellow starter switch wire, at the starter, when turning key to start.
4. since my car is a 6 speed, my yellow switch wire, coming off ignition switch, is spliced, for the clutch switch. So coming off the ignition switch, when key turned to start, i see voltage.

Might my problem be the Passkey/VATs system? From the wiring diagram, the yellow wire from the ignition switch goes to the module. I suppose i could make sure I dont' have a break in my starter switch wire, somewhere under the engine bay.

One other question - the wiring diagram suggests (for the (9C1 police) you can simply run the yellow wire from the ignition switch directly to the starter and completely bypass the VATs. Has anyone done this?
 

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Take all necessary safety precautions. (brakes on, in neutral, and others)

Turn key to run. Run a wire from the starter battery cable to the yellow wire stud this will crank the engine.

If the car starts and runs you have a issue with the starter circuit. If it just cranks you have a VATS problem. The light would tell you that it may not be sending the PWM to the PCM.

The Four VATS Modes:

VATS sees a correct resistor value, powers the VATS/starter relay to allow cranking, and sends a PWM signal to the PCM.

VATS sees a open circuit, lights the VATS light, powers the VATS/starter relay to allow cranking, and sends a PWM signal to the PCM.

VATS sees a bad resistor value, does NOT power the VATS/starter relay to allow cranking, and does NOT send a PWM signal to the PCM.

The engine is running and the resistor signal becomes bad. The engine will run and the VATS light will be turned on.


The other quick test is to unplug the key cylinder from the VATS. The VATS should let you run the engine then.


One other question - the wiring diagram suggests (for the (9C1 police) you can simply run the yellow wire from the ignition switch directly to the starter and completely bypass the VATs. Has anyone done this?
The 9C1 still has a VATS. The key resistor value is a wire loop.(dead short) The VATS still sends the PWM to the PCM. Yes the starter relay is missing.

When the VATS is programed out of the PCM this is part of the mod. Some people also just power the relay from the VATS wire harness.
 

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Discussion Starter #3
Yellow stud?
 

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3. no voltage at the yellow starter switch wire, at the starter, when turning key to start.
Use a big wire to connect the battery starter wire to the starter solenoid connector on the starter which has the yellow starter wire normally attached. (on most cars a stud and nut) This will crank the engine.:wink2:
 

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Discussion Starter #5
Use a big wire to connect the battery starter wire to the starter solenoid connector on the starter which has the yellow starter wire normally attached. (on most cars a stud and nut) This will crank the engine.:wink2:
Thanks man. Just making sure I do it right - you mean i should leave the yellow wire attached at the starter or disconnect it? and basically just 'jumper' the two connections at the starter (heavy wire from the B+ connector to the switch connector)? Or should i run a separate leg from the positive terminal to the switch connector? or does it matter?

One more question - does $eeHack have a VATS select/ECM switch capability? I know it has some controls but limited writing.

Thanks-
 

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One more question - does $eeHack have a VATS select/ECM switch capability? I know it has some controls but limited writing.
I have not tried $EEHack. It sounds great but he explains that he adds code to the PCM and stores extra information as well. Since I am not sure that Tunner Cat will erase or write over the extras I will only try it on a spare PCM.

should leave the yellow wire attached at the starter or disconnect it? and basically just 'jumper' the two connections at the starter (heavy wire from the B+ connector to the switch connector)
Yes leave the yellow wire attached at the starter.Yes just 'jumper' the two connections. Please read the ramblings below for extra information.

When I was checking in the injector information I found a easy way if you have a scan tool. The VATS fault will not turn on the MIL light But it will set DCT 46 (OBDI 46) If you find this you will have to work your way through the VATS circuit.

The other quick test is to unplug the key cylinder from the VATS. The VATS should let you start and run the engine then.

If you can not scan it what I am suggesting is a $0.10 bump switch.

In the good old days when things were simple we needed to rotate the engine to adjust valves, find top dead center, ect.

We would go to Sears or K-Mart (or Snap-On) and get a pre-made switch with wires with electrical clips on the wires. Clip one to the battery and the other to the starter solenoid. Push the button and the engine would crank. If the ignition switch was on run the engine would start.

The $0.10 version is a 4 inch piece of 12 ga wire. Gloves and glasses for safety. Prep the car for starting, then set the ignition to run, Press one copper wire end on the starter's battery stud. Get ready for cranking and press the other copper end to the solenoid's stud on the starter. (sparks will fly do not worry) Hold the wire firm. Remove wire when the engine starts.(or not) Touching the wire to anything else will heat the wire and may start a fire.

You do not have to remove any wires from the starter.

In the bad old days before column locks and computers thieves would clip a wire to the battery and clip the other end to the spark coil. Under the car they would jam a wrench on the two starter studs. The engine starts and the car disappears.

If you do not think this is safe ask some one who works on old cars for a starter/bump switch. They were also part of a kit that would have a dwell/tac meter, and a timing light.

The idea is to totally bypass the starter circuit. The wire is your very crude starter switch.

Touch the wire, engine starts, and you know that the VATS is sending the PWM signal to the PCM which allows the PCM to run the fuel injectors. No VATS signal it may start but it will stall.(no fuel injection after cranking)

If it starts you will still have to sort out what is not passing the start signal. In your case you can start at the column switch, check the clutch switch, and (hardest) check at the VATS/starter relay.

Click on this:

Goldsswagon

Look at starting circuit and pass-key diagrams on Goldsswagon's site.
 

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Discussion Starter #7 (Edited)
Just got back in town and jumpered the battery B+ over to the switch, with the key in RUN. Starts right up and runs fine. Looking at the wiring diagram, the yellow wire (circuit 575) coming from the theft deterrent relay might be bad, from connection A2 ? It seems as though the Fuel Enable Output is fine, but the starter enable output is not. The clutch switch is fine and the column switch is also fine (i get 14V when turning key to start, at the yellow wire coming from ignition switch.

I am now thinking the theft deterrent relay, as the fuel enable circuit doesn't go thru this, but only the starter enable circuit.

thanks-
 

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If I ever take the dash off I think I will replace that relay.

The good thing is we diagnosed the VATS with a piece of scrap wire. We could have used a code reader voltmeter, or a oscilloscope. These systems are not hard to fix at home if you sort out the logic.

I would have bet on the clutch switch. I always use the clutch switch to power a relay. I do not think they like the high current of the starter circuit.

The clutch switch would have been the second place I would have tried a jumper wire.
 

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Discussion Starter #9
So why not just run a new yellow wire from the clutch switch down to the starter switch, at the starter, bypassing that relay?
 

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Discussion Starter #10
The relay is too damn hard to get to!
 

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the wiring diagram suggests (for the (9C1 police) you can simply run the yellow wire from the ignition switch directly to the starter
Now that you know the VATS will let you run the engine you could rewire the starter circuit.

Column to clutch switch to starter may work. Again I am not sure the T56 clutch switch can handle the starter current. If I find some time I will check diagrams at the library.
 

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Discussion Starter #12
Now that you know the VATS will let you run the engine you could rewire the starter circuit.

Column to clutch switch to starter may work. Again I am not sure the T56 clutch switch can handle the starter current. If I find some time I will check diagrams at the library.
I think it will be fine - the wire gauge in that clutch switch is equivalent to the yellow starter switch wire. In fact, my clutch switch works sporadically, mostly to the 'good', letting you start the car without clutch engaged, like 'the good old days'... (or was it 'the bad old days'?)...;)

If I get some balls, I may try putting in another relay, but its a PITA getting to it, under the dash. I did it once on my roadmaster wagon, but it didn't have the clutch pedal bracket from BBHP. That takes up space.

RT
 

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Discussion Starter #13
Well, so much for it being the theft deterrent (starter) relay. I put a known good one in (swapped out with my 96 RMW) and it did not start. Then, I decided to jumper, on the relay, connector 30 and connector 87 (these are the two large gauge yellow wires coming in to the relay). Car starts right up. So am thinking it still could be the theft deterrent module not sending the start enable signal to the relay, to make the connection. But could the module be 'bad' on the starter enable circuit side and be 'good' on the fuel enable circuit side?

Any other thoughts?
 

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Congratulations on getting to the relay. So many forum member describe the relay as impossible to get to.

You have very little left to do:

Check #85 for +12V with the key in start.

Find a +12V source for your tester. Then check for -12V on the #86 when you turn the key to start.

If you not get -12V at #86 try the yellow-black wire on the VATS check for -12V when you turn the key to start. If the signal is at the VATS you have a wire problem.
If there is no signal at the VATS you could unplug then plug back in the connector.(then recheck) Last check would be to clean the ground connector G104.

G104 is the problem child connector for the PCM, ICM,fuel pump, and many more.
Location: Engine compartment on front of left hand cylinder head. (coil bracket area)
Small black wires on a large ring terminal on a (3/8?) stud.

If none of this helps it is time to bypass the #30 to the #87 with a jumper or replace the VATS.

If you are going to get a junk yard VATS start a new thread. There will be more testing, and new keys with different resistor pellets.(1 in 15 chance it will be the same)

I would like to point out you have spent 4-10 hours on this. Time under the car, time taking off the dash pad ect. Fixing these cars is not easy and the OBD system will not always help.

I too like to have things working and factory. I hate duct tape, unmarked wires, and extra holes in the sheet metal.
 

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Discussion Starter #15
Congratulations on getting to the relay. So many forum member describe the relay as impossible to get to.
Wasn't so bad - about 45 minutes to remove the damn thing. You don't have to remove dash.

You have very little left to do:

Check #85 for +12V with the key in start.

Find a +12V source for your tester. Then check for -12V on the #86 when you turn the key to start.

If you not get -12V at #86 try the yellow-black wire on the VATS check for -12V when you turn the key to start. If the signal is at the VATS you have a wire problem.
This part I don't understand. Do you mean I need to find a 12V+ source for the + side of my DVM, and connect the negative side of my DVM to #86 on the relay? Why would it show negative voltage when I have the + side connected to a +12V source? I get the yellow purple wire experiment, and the unplug/plug experiment.

If there is no signal at the VATS you could unplug then plug back in the connector.(then recheck) Last check would be to clean the ground connector G104.

G104 is the problem child connector for the PCM, ICM,fuel pump, and many more.
Location: Engine compartment on front of left hand cylinder head. (coil bracket area)
Small black wires on a large ring terminal on a (3/8?) stud.

If none of this helps it is time to bypass the #30 to the #87 with a jumper or replace the VATS.
So I for sure wouldn't replace VATS, but if you simply jumper the two yellow wires going into and out of the relay, presume you'd just cut them at the relay and butt splice together (no room to solder up there). Would you leave the relay plugged in or unplugged - in other words, would having it one way or the other affect anything on the ability to start?

If you are going to get a junk yard VATS start a new thread. There will be more testing, and new keys with different resistor pellets.(1 in 15 chance it will be the same)

I would like to point out you have spent 4-10 hours on this. Time under the car, time taking off the dash pad ect. Fixing these cars is not easy and the OBD system will not always help.

I too like to have things working and factory. I hate duct tape, unmarked wires, and extra holes in the sheet metal.[/QUOTE]
 

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Discussion Starter #16
Congratulations on getting to the relay. So many forum member describe the relay as impossible to get to.
Wasn't so bad - about 45 minutes to remove the damn thing. You don't have to remove dash.


You have very little left to do:

Check #85 for +12V with the key in start.

Find a +12V source for your tester. Then check for -12V on the #86 when you turn the key to start.

If you not get -12V at #86 try the yellow-black wire on the VATS check for -12V when you turn the key to start. If the signal is at the VATS you have a wire problem.
The second part of this test I don't understand. Do you mean I need to find a 12V+ source for the + side of my DVM, and connect the negative side of my DVM to #86 on the relay? Why would it show negative voltage when I have the + side connected to a +12V source?

If there is no signal at the VATS you could unplug then plug back in the connector.(then recheck) Last check would be to clean the ground connector G104.

G104 is the problem child connector for the PCM, ICM,fuel pump, and many more.
Location: Engine compartment on front of left hand cylinder head. (coil bracket area)
Small black wires on a large ring terminal on a (3/8?) stud.

If none of this helps it is time to bypass the #30 to the #87 with a jumper or replace the VATS.
So I for sure wouldn't replace VATS, but if you simply jumper the two yellow wires going into and out of the relay, presume you'd just cut them at the relay and butt splice together (no room to solder up there)? Would you leave the relay plugged in or unplugged - in other words, would having it one way or the other affect anything on the ability to start?
 

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New first test for you. Find Fuse #24 (10A Crank Fuse). There should be a diagram on the back of the fuse cover or in the OM. Make sure there is +12 on both sides of the fuse while the key is in start and when the fuse is plugged in. You should be able to probe the two metal tabs on top of the fuse while the key is in start (crank).

If this fuse blew I would not put the original starter relay back in.(new relay time)

I should have suggested this before sending you under the car to the starter but I thought you had checked it.

Find a +12V source for your tester. Then check for -12V on the #86 when you turn the key to start.
The second part of this test I don't understand. Do you mean I need to find a 12V+ source for the + side of my DVM, and connect the negative side of my DVM to #86 on the relay? Why would it show negative voltage when I have the + side connected to a +12V source?
Sorry if this was not clear. I suggest constant a +12V source for your +(red) test lead. Just saying find a easy spot so it is easy to connect. The -(black) goes to the #86. You will not see a +12V voltage on the DVM until you turn the key to run/start. The VATS module switches the #86 to ground.

The electronic parts that switch a ground wire are ten times cheaper than the ones that switch positive power. This is why the fuel injectors, the transmission, and others are connected to positive power and the PCM completes the circuit by grounding the other wire.

if you simply jumper the two yellow wires going into and out of the relay, presume you'd just cut them at the relay and butt splice together (no room to solder up there)?
I would make a male-male quick connect jumper wire and replace the relay with it. Maybe a little tape in case the male quick connect tries to pop out of the relay socket. That way everything is stock.

cut them at the relay and butt splice together (no room to solder up there). Would you leave the relay plugged in or unplugged
If I had to do it that way I would remove the relay.

Tip of the day:
Use a test light. It proves that there is voltage and some current. When you test a circuit with corroded wires or ground connection the DVM may show perfect normal voltage. The test light draws power (amps) through the circuit and may show a problem (dimmer light).
A good example is one of the forum members was having trouble with the gas gauge. When he finally cleaned the ground connection the gauge worked and the power windows moved faster.(more voltage under load) A volt meter can give crazy readings when you have a tail light grounding problem. The test light is easier to use.
 

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Discussion Starter #18
So here's what I found.

1. Fuse #24 test is just fine. It shows 0V on both sides of fuse when Key is in RUN and then +12V when key is in Start, on both sides.

2. When doing the test on #85, it goes to +12V when key is in START, as it should.

3. But upon doing the test for #86 (and using battery B+ as source), it shows +12V when key is in RUN. Switching the Key to START doesn't change the voltage - it stays at 12V. Does this mean the module (not relay) is bad? (By the way, it does show 0V when key is in Off position).
 

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I put a known good one in (swapped out with my 96 RMW) Good Quick check
I decided to jumper, on the relay, connector 30 and connector 87 (these are the two large gauge yellow wires coming in to the relay). Car starts right up.
Assuming you put the jumper wire into the relay socket. We know the high current part of the socket works. (pic1)
1. Fuse #24 test is just fine. It shows 0V on both sides of fuse when Key is in RUN and then +12V when key is in Start, on both sides.
2. When doing the test on #85, it goes to +12V when key is in START, as it should.
Good tests.
3. But upon doing the test for #86 (and using battery B+ as source), it shows +12V when key is in RUN. Switching the Key to START doesn't change the voltage - it stays at 12V. Does this mean the module (not relay) is bad?
No, it means the module should power the relay. I have not checked when the module powers the relay but it makes sense that it occurs when the key is in run and start.
(By the way, it does show 0V when key is in Off position).
This confirms the module is switching the voltage on and off.

So you have run the tests and they are all good. What now?
I put a known good one in (swapped out with my 96 RMW)
Did you try the starter relay in the RMW? If it works in the RMW we can take a relay problem out of the equation.
To be double shure power a relay straight off the battery #85+ and #86-. The click is a good sign. If your meter will do ohms check that #30 and #87 are close/=0 with the relay on.
Pop a good relay back in the relay socket. Turn the key to run. Did you hear a click. If yes the module and the relay are working together.

If it clicks you can back probe the relay socket and again confirm voltage at #87.(pic2) If you can not back probe pierce the wire then tape it after.

If the clutch switch is between the relay #87 and the starter you are back to checking it out.

With the test you have done the relay should be powered by the module. Has the car shown any other signs of gremlins? :eek:
 

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Discussion Starter #20
So I just did the relay click test, for good measure and yes, the relay clicks when you run + to 85 and - to 86. also verified no voltage between 30 and 87 while relay is 'ON'.

To answer your other question, yes, i swapped out the relay from my 95 SS to my RMW, and the relay did work in my RMW (but I should mention that my PassKey light has been on steadily in that car for over two years and no issues whatsoever with starting or running).

The clutch switch is 'before' the relay, between it and the ignition switch.

I had no other gremlins before this incident.

On doing the test for #86 to B+, my Factory Manual states that to
1. disconnect theft deterrent relay.
2. attach a test light between theft deterrent relay connector terminal A1 (which is 86) and B+
3. While observing test light, turn ignition switch to START
4. Does light illuminate?

This would imply that unless the ignition is turned to START, the light wouldn't illuminate (no current/voltage). But in my case, i am seeing voltage across A1 (86) and B+, in RUN. Which i don't believe should be happening, correct?

And when i pop the relay back in, i hear no click.
 
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