[SOLVED] The strangest problem I have ever encountered on a project - Crank, no start, no gauges, weird issues. Help!

[Firebirdracer82]

Sadly my scanner is like one of those little ones you can get at the auto parts store. Had it for years, but it doesn't show too much. It doesn't pull up any codes at all.

The cluster doesn't show RPM cranking, I can't remember from my last Tahoe if the tach jumped on cranking or if it waited until it started.

I could use my multimeter to see if there is continuity to ground at the negative post from terminal B possibly, but I am not sure if I would need to crank it or not while doing so to see ground signal there.

I'm wondering if there are other symptoms I should be looking for. A crank sensor would be easy, but throwing parts of this might not be my best idea.

 

[Firebirdracer82]

1. Check INJ 1 and INJ 2 Fuses (Underhood).
2. Swap IGN Relay (Underhood).
3. Confirm Tachometer movement during cranking.
4. Inspect CKP Sensor wiring above the starter.
5. Verify 12V on the Pink wire at any coil.
6. RE-CHECK THE GROUND FOR THE HEAD/S

1 - Will give that a shot in the morning and see.
2 - same
3 - NO tach movement cranking.
4 - will start on that tomorrow morning. For $30 I might grab one from auto zone to test.
5 - Pink wire has power with test light - will measure it in the AM.
6 - are you talking about the braided strap? I can use a set of jumper cables as a temp ground and see if that makes a difference. I've going through it with a multimeter and it seems to be OK, but I haven't checked it for resistance.

 

[LsHart]

About the car:

2004 Yukon - 185K miles. It had been sitting a long, long time. I thought that I could cure it with some common fixes, but, alas, I cannot.

Symptoms:

Crank, no start was the initial issue.

If you get in the truck, put the key in, and turn it to "on", before cranking, then the electronics don't work (mirrors, windows, locks, radio, climate control). The headlights don't work, except for the rear lights and one marker light in the front - no headlights either.

It will crank, but won't fire.

But, if you turn the key to off after you crank it, with the door closed, the electronics work (locks, mirrors, windows, radio, headlights - etc.). I believe this is the RAP system.

Cluster is broken and not working at all. I only have the check engine light on the cluster.

THINGS I HAVE DONE DO FAR:

1.) Cleaned the grounds and charged the battery. Verified no spark on crank.
2.) Cleaned PCM connections.
3.) Ordered a new BCM programed to the vin. Installed. Did key relearn - it is recognized since I am getting chime now when the key is left inside the car.
4.) Checked fuses, but perhaps I should check them again.


What do I do next? Help? I am trying to get a working cluster as well to assist in this situation. I do not have a bi-directional scanner - just a simple code reader.

Check the main max fuse at the fuse box under the hood?

 

[Firebirdracer82]

Check the main max fuse at the fuse box under the hood?

I’m not sure which one that is, I went through them with a test light though. Including ign a/b 40 amp ones

 

[LsHart]

I wanna say without looking it's a 125 amp power fuse. On the engine side of fuse box.

 

[LsHart]

I wanna say without looking it's a 125 amp power fuse. On the engine side of fuse box.

I just went out to mine and there are power fuses. U have a power feed issue. When u go in the scanner to each module, is there one that says no communication?

 

[Jimmyy]

I had a crank no start on my 2006. It ended up being the wires going to the crank sensor. I also found wires under the fuse box chewed up by mice. There's a small access they can get under the fuse box and chew up the wires.

 

[strutaeng]

For injector pulse, I've used an LED test light. No need for noid lights, as dar as I know on these engines.

 

[LsHart]

I suggested noid lights as a means of diag for driver misfires. Fords are bad about it.

 

[Firebirdracer82]

I just went out to mine and there are power fuses. U have a power feed issue. When u go in the scanner to each module, is there one that says no communication?

Sadly my scanner can’t really do that. And none of my friends on their own work. I’ve might check if the auto parts store would let me borrow one but they didn’t have anything complicated last time I asked to be borrowed.

 

[Firebirdracer82]

I had a crank no start on my 2006. It ended up being the wires going to the crank sensor. I also found wires under the fuse box chewed up by mice. There's a small access they can get under the fuse box and chew up the wires.

That was one of my first thoughts but went through the fuse box and took it apart. Cleaned the connections. No mice and pretty clean

 

[Firebirdracer82]

Update for the morning:

Cleaned grounds on left side of engine block, for peace of mind. - no change.

Used test light on a fuel injector - I cannot figure out how to get it to sit to see if there is a pulse, but one wire has power at least, may use multimeter to go back a verify ground on the other prong.

Verified that my throttle body was going with my gas pedal. Since its the electric throttle body I was assuming that it would run through the PCM, and that maybe if I verified that was working I could figure it wasn't the PCM, but I don't know.

 

[Firebirdracer82]

Basically I think at this point I am trying to decide between PCM, crank position sensor and some wiring problem I haven’t found yet.

 

[Firebirdracer82]

1. Check INJ 1 and INJ 2 Fuses (Underhood).
2. Swap IGN Relay (Underhood).
3. Confirm Tachometer movement during cranking.
4. Inspect CKP Sensor wiring above the starter.
5. Verify 12V on the Pink wire at any coil.
6. RE-CHECK THE GROUND FOR THE HEAD/S

Performed part of this:

1. Fuses appear good. Switched them around with others. No change.
2. Swapped ignition relay with horn relay, no change.
3. No RPM when cranking
4. Possible next with sensor change.
5. Verified
6. Checked.

I think it’s either the PCM or Crank sensor or wiring and I am trying to decide between the two.

 

[Joseph Garcia]

Performed part of this:

1. Fuses appear good. Switched them around with others. No change.
2. Swapped ignition relay with horn relay, no change.
3. No RPM when cranking
4. Possible next with sensor change.
5. Verified
6. Checked.

I think it’s either the PCM or Crank sensor or wiring and I am trying to decide between the two.

I know that this won't help you in your current situation, due to your timing constraints, but for the future, you should consider this, as it would have most likely pinpointed the source of your current issue.

I recommend that you get yourself a quality bi-directional scanner to add to your tool box. Then, you will be able to read ALL trouble codes, along with a brief explanation/pointer to the source of your issue. You can test many of the truck's electronic functions with the scanner, in order to determine the source of an issue. You will also be able to reset/delete trouble codes, after taking corrective action. You will literally save thousands of dollars in diagnostic and repair costs over the life of your truck, and you will most likely recoup the cost of the scanner within 1 year.

 

[Firebirdracer82]

I know that this won't help you in your current situation, due to your timing constraints, but for the future, you should consider this, as it would have most likely pinpointed the source of your current issue.

I recommend that you get yourself a quality bi-directional scanner to add to your tool box. Then, you will be able to read ALL trouble codes, along with a brief explanation/pointer to the source of your issue. You can test many of the truck's electronic functions with the scanner, in order to determine the source of an issue. You will also be able to reset/delete trouble codes, after taking corrective action. You will literally save thousands of dollars in diagnostic and repair costs over the life of your truck, and you will most likely recoup the cost of the scanner within 1 year.

You are absolutely right but after this purchase probably not in the budget for a few months sadly.

 

[Doubeleive]

@rockola1971 any idea's here regarding the PCM to injector signal

 

[Jimmyy]

I don't know if I missed something, but if you have no spark I would start there. You could give it some starting fluid to bypass a fuel issue.

 

[Firebirdracer82]

@rockola1971 any idea's here regarding the PCM to injector signal

Honestly don't know how to test that without a node light. I can pull an injector plug and my test light shows one terminal has power and can verify that the other has ground in the future.

Would it work, with the terminal removed, to have my test light go between one side and the other, and then have someone else crank it? Would that verify injector signal if it pulsed?

 

[Firebirdracer82]

I don't know if I missed something, but if you have no spark I would start there. You could give it some starting fluid to bypass a fuel issue.

It's definitely, in part at least, a spark issue. I have fuel pressure, and main power to the coils, but I don't believe I am getting a pulse signal.