More non-start - my Riv's specialty!

Same thing as always, accesories have power, but the starter motor won't crank. I can hear a click when I turn the key to "start." The battery tested good at Autozone. While I had it out I cleaned the connectors good. At one point I thought I had found the problem - the take off wire from the positive battery terminal to the fuse boxes was totally loose on the fuse box end! I tightened it down, but it turned out that wasn't the problem. A buddy of mine jumped the starter motor - it works when it gets juice, but with the key in the start position the starter motor won't crank the car when jumped. It makes an odd "nnnnnt" sound but doesn't do anything. My buddy didn't think the problem was with the starter or starter solenoid, but possibly a sensor or the pellet in the key. I tried the other key set (no luck), and the car isn't showing any codes.

Any ideas?

97 Riv SC, battery is an Optima Red Top. No engine mods. The car started and ran great, before it didn't.

Did you follow the flow chart in the FSM ? I gave mine away with the car so I can`t look up the riv specific one for you but it should be called something like "starting diagnosis - starter solenoid clicks engine does not crank"

It requires the use of a DVM. there should be 3 outcomes:
replace positive battery cable
replace negative battery cable
replace starter assembly

IIRC if it were the VATS, wouldn't you get the "security" light ?

Start with the basics, man. Here's the entire "Starting" schematic for a '97. Check the fuses, check the relay, ground and power.

Jason wrote:

Did you follow the flow chart in the FSM ?  I gave mine away with the car so I can`t look up the riv specific one for you but it should be called something like "starting diagnosis - starter solenoid clicks engine does not crank"

It requires the use of a DVM.  there should be 3 outcomes:
replace positive battery cable
replace negative battery cable
replace starter assembly

IIRC if it were the VATS, wouldn't you get the "security" light ?

The security light turns off when the key is in top two positions (on and start). The light is on in the lower positions, and if the door is open and the key is not in the ignition. That means VATS is working, right?

DVM is Digital Volt Meter?

I don't have the FSM but it looks like Abaddon is here to help.

I replaced the negative battery cable with the optima, so I'm guessing that's not it. The starter works if jumped. If sensors aren't a possibility (no codes showing), than that leaves the positive battery cable. I'm not going to be surprised if that's it. I've been cleaning corrosion off the end ever since I got the car. I don't think it's normal. Whatever it is may have worked up into the cable and caused a failure somewhere.

Abaddon wrote:

Start with the basics, man. Here's the entire "Starting" schematic for a '97. Check the fuses, check the relay, ground and power.

The ignition fuses are good, there's a clicking in the fuse box which I assume is the relay. I don't think there's anything wrong with the ground cable, so again that leaves the positive battery cable, right? You don't think there could be a sensor or ignition module problem without codes either?

Jack the R wrote:

Same thing as always, accesories have power, but the starter motor won't crank.  I can hear a click when I turn the key to "start."  The battery tested good at Autozone.  While I had it out I cleaned the connectors good.  At one point I thought I had found the problem - the take off wire from the positive battery terminal to the fuse boxes was totally loose on the fuse box end!  I tightened it down, but it turned out that wasn't the problem.  A buddy of mine jumped the starter motor - it works when it gets juice, but with the key in the start position the starter motor won't crank the car when jumped.  It makes an odd "nnnnnt" sound but doesn't do anything.  My buddy didn't think the problem was with the starter or starter solenoid, but possibly a sensor or the pellet in the key.  I tried the other key set (no luck), and the car isn't showing any codes.

Any ideas?

97 Riv SC, battery is an Optima Red Top.  No engine mods.  The car started and ran great, before it didn't.  

Also detach battery from car at positive cable (under seat) and test with voltmeter, shouldbe above 12.2 v or so. Report the number please.

someone with a FSM should confirm but isn`t there a test that says
-ignition sw to Start
- use a DVM (digital volt meter) to measure voltage from battery positive terminal to starter solenoid terminal "X"

Voltage greater than .5V: replace + batt cable

Voltage less than 0.5V:
-ignition sw to Start
- use a DVM (digital volt meter) to measure voltage from battery negative terminal to ground "Y"

voltage less than 0.5V: replace starter assy
voltage greater than 0.5V: replace negative batt terminal

My neighbor's got a DVM and we're planning to test the car tomorrow. We know power is getting to the starter. Autozone tested the battery as good. I don't know what the exact voltage coming off of it is but I'll find out.

Tonight we have numbers -

Battery without + cable attached - 12.5 v

Battery with + cable attached - 12.04 v

Battery + cable @ starter solenoid - 11.8-12.2 v

Ignition wire (purple wire) @ solenoid, with key in start position - 0 v

12 v was applied to the ignition wire and the car cranked.

It looks like the ignition wire may be the problem as it is very loose and the connection is likely cruddy. I'll clean it tomorrow and tighten it back down - perhaps the car will start, or perhaps the loose ignition wire will prove to be another problem that was developing and not the one I'm after this time.

I fixed the ignition wire connection, but still, no start.

We've ruled out a lot of things. What's left?

Have you tried swapping to a known good relay? Just pull one from a different location and pop it in the starter spot.

Where is it? I'm not seeing a starter relay with the other relays, unless it's in the little box that's by itself on the far driver's side, under the passenger seat. Next to the two bigger boxes, one of which has fuses and the other has relays.

Starter Enable Relay

Behind LH side of I/P, on bracket left of steering column

Sry bout that....

I/P is instrument panel? I pulled the pastic cover the OBD port is in and looked under the dash. I saw a lot of connectors but I failed to spot the relay. Maybe I've got the wrong idea and it's actually on the back of the instrument panel?

It appears that it's attached to the bracket that holds BCM in place, which is above the hush panel with the DLC attached to it. Should be two 7mm screws that hold on the DLC.
1) BCM
2) Starter Enable Relay

Is there another one like that somewhere else in the car, or am I in "throw money at the problem until it goes away" territory now?

Did you find the relay? It's up there. It's a giant PITA to get too if I'm not mistaken. With the schematic I posted, you can jump relay terminals C1 and A2 and see of the car starts. Or, start with C1 and see of you have 12V trying to start the car. If you have 12V there trying to start, you know that the Ignition Switch is ok.

No, there are no others like that in the car. That schematic is basically the entire starting system, given that VATS is operating normally.

This is the BCM, right?

What is A2?  I see it on the schematic you posted, but what does the part look like?

By the looks of it, the Relay is mounted left of the BCM. So, its buried in the back corner of your picture. You may have to disengage the BCM from the bracket and lower it down to see the relay.
A2 is just one of the pins on the relay itself. Jumping pins C1-A2 bypasses the "energized" section of the relay. You're basically hard-wiring that circuit.

There's also that 10A CRANK Fuse in the IP fuse block that needs to be checked.

This guy with the green tab is the starter relay?

The crank fuse is good.

Let me make sure I understand what I'm seeing.  There are four wires going into the starter relay, two yellow wires and two purple wires.  Are C1 and A2 the two yellow wires?

How do you test the wires with the DVM?  Referring to this illustration -



The starter relay ends in a single tab.  But in the pic I took it looks like there is a black piece that plugs into a grey plastic piece.  If I pull the black piece, maybe there are four little metal tabs on it?  I guess then I would test the tab of the smaller yellow wire (C1?) to see if it's getting 12v, and then jump the two yellow wires to see if it will crank?

You found it! Cool.

Forget about the illustration now. Let's focus on the schematic. YEL means Yellow. PPL means Purple.
C1 is yellow, A2 is purple. What I want you to do is unplug the relay so that just the connector is in your hand. You'll need to release that green CPA (lock tab) before you can physically unplug the connector. That lock tab pulls down towards you. It might be a bitch to get out. Remember, it's been in there since the car was new and probably never been touched. When you get it unplugged, it will look like the pic below. This makes it WAYYYY easier to test.


Pin
Wire Color
Circuit No.
Function

A1
YEL
575
Vehicle Anti-Theft System Starter Enable Relay Output - Normally-Open Contact

A2
PPL
6
Starter Solenoid Feed

B1- B2
—
—
Not Used

C1
YEL
5
Ignition Switch Output - Crank

C2
PPL
806
Fuse Output - Crank - Type III Fuse

Sorry it's big, but it wouldn't let me save this pic. I took a pic of it with my phone and emailed it to myself
With the schematic and this connector end view, we can figure out if the relay is good, and we have power and what-not to it. All tests can be done on the connector itself. If you have 12V in all the right places (ignition "ON"), you can jump C1 and A2 with a piece of wire on the connector and see if the car starts.

Jack the R wrote:

I fixed the ignition wire connection, but still, no start.  

We've ruled out a lot of things.  What's left?

Consider replacing that + cable, with a good junkyard cable out of a near-year Cadillac, Park Ave or Riv. I bet you will find other issues along length of the old one.  I am not certain there should  be 1/2 V drop in a 0000-gauge cable for that length, and with the corrosion you say you are chasing odds are the resistance of that cable goes up when you run high current thru and it heats up. I would not keep messing with it.

Good news! The Riv started flawlessly when I jumped the starter relay. Voltage at C1 was 11.8 -11.9. That means the starter relay needs to be replaced, right?

albertj - Yeah, I think the + cable needs to go too. Considering how many other problems I've found along the way (loose cable at the fuse box, loose cable at the starter solenoid) maybe I should go over the entire ignition system.

Jack the R wrote:

Good news!  The Riv started flawlessly when I jumped the starter relay.  Voltage at C1 was 11.8 -11.9.  That means the starter relay needs to be replaced, right?

Yay!

In theory, yes. As long as the PNP switch knows the car is in park (or neutral), that relay is your problem.
One more thing......
You said the CRANK fuse was good, so you should have 12V on C2 as well.
As for A1, that's what physically energizes the relay to close the contacts on A2 and C1 to start the car. The VATS will ground that circuit, thus completing it. Easy check for this is to plug the relay back in, and backprobe the connector with a DVOM. You should have 12V at A1 and C2 with the key in the CRANK position. If both of those terminals have 12V during CRANK, then yes, the relay is bad. If you only get 12V on C2, and nothing on A1, then either the PNP switch is bad, or VATS is preventing the car from starting. I'd be inclined to think that VATS would toss a SECURITY light if this were the case though.

So, just at that relay connector, you can diagnose the entire top half of the starting circuit. Fun, eh?

Abaddon wrote:

You said the CRANK fuse was good, so you should have 12V on C2 as well.

Was the 11.8-11.9 I got on C1 close enough?  It sounds like 12v is what it should be.  My reading was bouncing around a bit so maybe there is a margin of error and it could be 12v, for all I know.

Abaddon wrote:

As for A1, that's what physically energizes the relay to close the contacts on A2 and C1 to start the car. The VATS will ground that circuit, thus completing it. Easy check for this is to plug the relay back in, and backprobe the connector with a DVOM.

DVOM?  You mean DVM, right?  

Abaddon wrote:

So, just at that relay connector, you can diagnose the entire top half of the starting circuit. Fun, eh?

I think it's pretty cool stuff.  If I'd known all this stuff a couple weeks ago I could have saved myself an $80 tow.

Where can I get the relay from?  Rockauto doesn't have it.  What's involved in changing this thing out?