Ralphbf

Okay I checked the threads here, I purchased an almost useless Haynes shop manual.

New starter
I can hear the fuel pump working
Engine won't crank

Where is the starter relay?

Thanks

Ralpj

AGENT 86

Might help knowing what year ?

jfb

Can you hear the starter solenoid click? The only relay in the starter circuit is the VATS enable relay whick allows 12v from the crank contact on the ign sw to get to the starter solenoid.

Ralphbf

It's a 1990

Turn the key on and you can hear the fuel pump.

The starter seems dead. No nothing from it.

I can jump the starter and it cranks.

I understand there is a relay just for the starter and that is what I can't find.

Thanks again

Ralph

hooked073

are you thinking of the solenoid? take a test light see it you have 12 volts on the s term of the solenoid while key is turned to crank. If you have 12 volts it is solenoid if not have to look futher.

Ralphbf

......I can jump the starter and it cranks.

Meaning it turns the engine over just fine.

My manual says there is a " Starter Interrupt Relay"

And that is what I'm looking for.

Ralph

Hooked on Vettes

You never stated what transmission you have.
The schematic shows the starter current path for a manual transmission.

If you have an auto the current path goes thru the
Park/neutral switch instead of the clutch safety switch.

Ralphbf

That one did slip by.
I have the 6 speed.

I'm simply looking for the physical location of the

Clutch start switch aka " Starter Interrupt Relay"

I know the clutch switch is working because the fuel pump works.

Ralph

hooked073

Sorry misread

C409

...... Sounds like a VATS issue ... starter enable relay is activated by the ECM after receiving clearance from the VATS module which , in turn , needs to "see" the proper resistance pellet on the ignition key in order to allow the car to start ... BTW : Vehicle Anti Theft System .......

Hooked on Vettes

The starter enable relay is shown in the picture above.
It's a relay under the driver side of the dash cluster. The CCM
grounds the primary of the relay coil to energize the relay.

The clutch safety switch has nothing to do with the fuel pump.

When you turn the ignition key to start, 12 volts from the ignition
switch goes to the starter enable relay. If the key pellet resistance value
matches what the CCM was programmed for, the CCM will ground
the primary coil of the starter enable relay. The relay closes and
12 volts passes thru it to the Clutch Safety switch. If the Clutch pedal
is depressed, the 12 volts passes thru the switch to the Starter Solenoid
which is a Purple wire.

A defective Clutch Safety switch is a common problem. The contacts
inside the switch can't handle the current. The part is no longer available.
Some people bypass it.

When you turn the ignition key to On, does the Security light go Out or does it stay On?
If it stays on, the key pellet resistance is not being read properly by the CCM so the
starter will not engage.

You need to gain access to the starter enable relay. By taking some voltage
measurements at the starter enable relay socket it will lead you to what the problem is.

Remove the panel that contains the foot well lamp. You might also have to remove the
carpet that covers a metal panel that is bolted under the steering column. This will give
you access to the relay which is located under the front edge of the dash cluster.

Ralphbf

I don't believe it's the VAT system because the way I understand it it disables the fuel pump also.
Fuel pump is a working.

So My hopes lay it the
Clutch start switch aka " Starter Interrupt Relay"

But I could not find it any where, now I know where to look.

Thanks and I will keep the group updated.

Ralph

Hooked on Vettes

If the key pellet resistance value does not match what the CCM
was programmed for, the starter will be disabled and the
computer will not pulse the injectors. The fuel pump will
still operate.

There is a starter enable relay and a clutch safety switch.
They are two individual parts.

Ralphbf

The easy fix would be the Clutch start switch aka " Starter Interrupt Relay" ?

jfb

The VATS system measures the resistance of the pellet in your ignition key and if it is within 4% of the assigned value, it closes the start enable relay allowing 12v to continue from your ign sw crank contact on to the clutch safety switch and then to the starter solenoid. The VATS circuit will also allow the CCM to pulse the injectors so the engine can start and run. VATS does nothing to the fuel pump!
The start enable relay is behind the, "breadbox" on the right side of the dash. Most VATS problems are due to a defective clutch safety switch (jump yours and try a crank) or the contacts in the ign lock fail to make connection to the key pellet. I have replaced the ign lock three times on my 87 vette which have new contacts and I have permanently bypassed my defective clutch safety switch, but even with 240k miles and driven every day, my start enable relay is original. If I were you, I'd forget about the relay and concentrate on the clutch safety switch and also measure the resistance with the key in the lock on the two wires from above the steering column that go to a 2 pin connector. Unplug the 2 wires and measure the resistance across them with the key inserted. It should measure the same as the pellet.

Ralphbf

It was the starter interupt relay.

What a PAIN.

Thanks to all.

Ralph