More questions about security and starting Grand Am 2004

EaOutlaw

Active member
1,304
2
36
what manual did you get?

where do the wires from the ( mystery) connector go to, near the instrument cluster, radio, HVAC ?
 

EaOutlaw

Active member
1,304
2
36
After checking out the website I am really suspicious that the wiring diagram you may be working from may be wrong.

When you get a factory service manual it covers one year with other makes that are identical.

If you look up the OEM service manual it covers the 2004 Grand AM and the Oldsmobile Alero.

http://www.ebay.com/itm/2004-PONTIA...m25b49f4379:m:ma0-OsEUYbWUAH0RZ5t1BBQ&vxp=mtr

As you can see this manual spans two printed copies, the link you provided claims it includes Pontiac Grand Am from 1999 to 2005.

I am thinking they may have merged some of the data. causing you to work from a incorrect wiring diagram.

Some of the content may be relevant and or accurate as far as replacing parts and what not.

Yet there is no way in the world I would trust this manual to provide accurate and complete information to be used for diagnostics.

If I were you, I would sign up for Alldata. and start reading any related TSBs for condition your car has.

If I didn't find anything relevant I would start tracking down the problem with the diagnostic flow chart for engine not cranking.

Then use the provided OEM wiring diagrams for the 2004 Pontiac Grand Am ( referencing ) the connector locations as well to get to the bottom of your problem.

If the suspect connector does not show up on the known good diagrams.

You may be able to track it down by just removing the instrument cluster which should be pretty easy.

Since I am not there, and its your car that will have to be your judgement call.

at least I would try to see if the mystery connection blue tab can be put back together securing the wires in the connector better.

However I am just going by what I viewed in the picture.

Also let us know if the wires are a different gauge and or color from the known OEM wires.
 

tjodork

New member
23
0
0
i tried to sign up for Alldatadiy.com on Friday ...it failed due to credit card issue....it finally worked today.
I got the schematic....its IDENTICAL.... my friend calls it the $30 schematic:)
I was waiting to do much until i got the schematic ...

Anyways...I will try taking the cluster off tonight and see if I can see the wires.
If all else fails, I am going to run a NEW wire from the fuse to the PCM (cutting the wire from the mystery connector
______________________________
 

EaOutlaw

Active member
1,304
2
36
since you have Alldata, why not diagnose the car with the flow chart for no cranking.
also look through the TSBs for anything related.
 

tjodork

New member
23
0
0
you're not going to believe this ...but one of the PCM connectors is backwards.
I can tell that the orientation for one is backwards.....but I want to be sure what is the right orientation.

Even though I have the ALLDATA web access, I cannot find ANYWHERE which connector is which and which end has pin *1*.

See picture....can anyone tell me which connector is C1 and which is C2 and which side is pin *1* for for both ? Sadly it seems GM does not make plugging connectors idiot-proof.

The schematics talk about a blue and clear connector but mine are both white.

I think the guy that worked on my car screwed this up big time.
 

Attachments

  • pcm connectors.jpg
    pcm connectors.jpg
    114.5 KB · Views: 51
Last edited:

EaOutlaw

Active member
1,304
2
36
The information you need should be found in Alldata, they normally have every connector with each pin location.

This would be confirmed by checking the color wires for each position.

Each connector should also be labeled. it may be hard to spot but you should see C1 and C2 on each connection the wires I would think should show up as this in the wiring diagram as well.

They may have it labeled differently than C1 and C2

I am pretty sure the car would not start up and run with either of the connectors not in the correct orientation.

What makes you think one of the connectors is plugged in the wrong way?

Did you fix the blue tab on the connector you couldn't find in the wiring diagram? the last picture you sent it looks seated better.

I will say it looks like someone has spent alot of time taking the connectors on and off the computer, it also looks like someone has been probing the wires with a test light.

It looks like a mess under there for sure.
 

tjodork

New member
23
0
0
here is a picture of what I have

the problem is EITHER connector could be backwards
so need to know right orientation for connectors and which is which
______________________________
 

Attachments

  • pcm connectors2.jpg
    pcm connectors2.jpg
    135.4 KB · Views: 50

EaOutlaw

Active member
1,304
2
36
Is the car still running? if so the connectors are correct.

Normally you can tell by the wiring it would be way twisted out of shape to get them connected wrong.

The pictures you are providing do not show the entire connectors.

see if you can get better pictures.
 

tjodork

New member
23
0
0
well.... connectors are not backwards.....my picture is right
GM just oriented the connectors 180 degrees
its clear when connectors are off...
should have taken off sooner...was nervous to do...
 

tjodork

New member
23
0
0
well after a lot of detours (figuring out correct pins on PCM connectors) ....
I'm back to the fact that the PCM Output called Starter Relay Coil Control (C2-76) is going low for a second and then going high.
The crank input to the PCM goes to 12V based on ignition switch turned to start so the PCM should be driving that Starter Relay Coil Control low.
The mechanic said the Output transistor/driver is weak and can't pull the signal low..
He wired a Normally open pushbutton switch to that signal and other side to ground.....to avoid buying a PCM (he said $500).

I might be happy with that situation but the I've been stranded several times where pushing the pushbutton cranks the engine over and over but it will not start...if I wait a bit it may start.

I found that I could buy a PCM off of ebay from a guy that will program it to your VIN for $80
http://www.ebay.com/itm/Grand-Am-20...-Programmed-to-your-VIN-/222006969116?vxp=mtr
He has 100% feedback rating.

I would buy the PCM in a second if I thought it would resolve the issue but I'm wondering if the computer was turning off that output (so wouldn't stay low) because of some other input
Is there any other inputs to the computer that affect the starter function.
Note I have bypassed the Passlock system with a resistor and no security light is on.
 

EaOutlaw

Active member
1,304
2
36
I still think you should locate the diagnostic flow chart for a no crank condition. start from the beginning.

I have been trying to help you with the diagnostics, I asked many questions during this process some have gone unanswered.

When you decide that a technicians word cannot be trusted because he said a expensive part needs to be replaced. you are the one that needs to diagnose the problem. this means if something has to be taken a part to figure out what it is then you have no choice but to do the work.

Guessing at this point by installing a computer will further complicate matters especially if the used 80 computer does not fix the problem or or worse creates a new one.

You said the wiring diagram found in Alldata is the same as the one you were working from, which I find strange because, the last diagram you posted had corrections scribbled on it.

If you are working from the correct diagram, with all the pages of the diagram involved there will be no mystery connectors.

If you really signed up for Alldata you will find a wealth of information, if you need help navigating this data let us know.
______________________________
 

tjodork

New member
23
0
0
ok, my task this weekend is to follow the diagnostics on the alldata web site
it had me pull DTCs and there are a lot - see attachment

due to DTC's it says to turn on key and use DMM Min/Max to capture intermittent conditions on Class 2 serial data circuit

that will be step 1
 

tjodork

New member
23
0
0
hmm no attachment - last post -oh too big
here are pics
 

Attachments

  • pic1.jpg
    pic1.jpg
    13.7 KB · Views: 45
  • pic2.jpg
    pic2.jpg
    166.2 KB · Views: 54
  • pic3.jpg
    pic3.jpg
    70.7 KB · Views: 46

EaOutlaw

Active member
1,304
2
36
if so clear them and re run the car then re scan for codes
______________________________
 

KYBoi6979

New member
21
0
1
your two connectors to pcm are blue and clear. Yes they both look whit until you carefully and halfway disconnect from protective casing. The connector closest to your break pedal is the one you want . When you flip the over and maneuvior around to back side (where pins go in) you will see on one end will start on top #1 and below second row #41 on the opposite end top #40 and bottom #80. if you find #1 and start there it ends on #20 >#41-#60 > (other end) #40-#21 > #80-#61. My problem was the purple wire pin#23 from PCM to the crank fuse under the hood. That was the only place through numerous tests that showed a significant drop in voltage, 1.3.
 

KYBoi6979

New member
21
0
1
My guess at this point is that when your probing pin 87 from the 40 amp fuse and not finding power, it is possible your not getting a good connection to the test light or meter.

Check for power at both sides of the fuse while someone is cranking the starter over for you. make sure the power is not disappearing under cranking condition.

If the voltage is present at the fuse on both sides of the fuse follow the wire to the next connector in line ( trace the wire from the fuse to the starter relay ) inspect any connector.

Pretty much you cannot have power to pin 30 without it coming from pin 87 unless you are working from the wrong wiring diagram.

Have you checked the fuse labeled Crank the 10 amp fuse located under the hood in position 54 it supplies the PCM with voltage during cranking.

again check this fuse on both sides of the fuse while someone is cranking the starter over for you.

I am thinking if the ignition switch drops the power to this fuse intermittently the PCM will not function to allow cranking. if you do have power during cranking the PCM may have a bad driver circuit as the tech suggested.

If it does drop power you may just be looking at a worn ignition switch.

So double check the power from the 40 amp fuse and check the power from the 10 amp fuse and let us know what you find
BINGO!!! When you asked "Have you checked the Crank Fuse #54 under hood compartment, which you are very correct, runs to the PCM under driver side dash, to the clear connector at pin #23(purple wire) Here is where I think my problem is coming from for no crank no fire up on same exact car! I am at this point at this very minute getting ready to replace this wire. The weather here is nasty so in the mean time just to check other thigs while i wait I am pulling the starter relay, run power to it to see if it engages.. If anyone has any other advice than what I have already done then please feel free to comment. Thank you
 

KYBoi6979

New member
21
0
1
Appreciate your input but have you noticed the 2016 date of this thread?
Thank you for noticing. Yes lol, I noticed the date on here but I am new to this forum and thought in some sense it would help ease myself in. Secondly, I am currently to date having this issue. The weather here has stopped my efforts for outside work. I have tested everything as slightly mentioned in my comment n due to the date of this post I was in hope someone would catch it quickly and may have more knowledge to share.
 
Top