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BOBBYSS
BOBBYSS, Master Technician
Category: Chevy
Satisfied Customers: 17277
Experience:  ASE MASTER CERTIFIED, AA DEGREE AUTO/DIESEL TECH
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Replaced PCM on 2002 chevy venture. Of course would not

Customer Question

Replaced PCM on 2002 chevy venture. Of course would not start. Performed the pass key 3 relearn. First cycle security light went out after 10 minutes. Second cycle security light went out after 10 minutes. Turned key to the on position for the 3rd cycle and it flashed instead of burned steady. Security light never went off even after 35 minutes.
JA: Thanks. Can you give me any more details about your issue?
Customer: tried to start the process over and now the light will not go out no matter how long I leave it on
JA: OK got it. Last thing — Chevy Mechanics generally expect a deposit of about $18 to help with your type of question (you only pay if satisfied). Now I'm going to take you to a page to place a secure deposit with JustAnswer. Don't worry, this chat is saved. After that, we will finish helping you.
Submitted: 1 year ago.
Category: Chevy
Expert:  BOBBYSS replied 1 year ago.

Hello, my name is***** you for the question. Can you give me the exact relearn you are using?

Customer: replied 1 year ago.
Turn key to run position. Let set until security light goes off. Then off for 5 seconds. Repeat this cycle times 3. But the security light will not go off.
Expert:  BOBBYSS replied 1 year ago.

Try this-

Turn the key on to the run position and leave it there for 10 minutes.

Turn the key off without removing it and then back to run for 10 minutes.

Turn the key off without removing it and then back to run for 10 more minutes.

After the third ten minute cycle turn the key off and then try starting it.

Customer: replied 1 year ago.
Turn off and then back on even in the security light does not go off correct?
Expert:  BOBBYSS replied 1 year ago.

Yes. Follow the time frames and not the light.

Customer: replied 1 year ago.
starting process now
Expert:  BOBBYSS replied 1 year ago.

Thanks.

Customer: replied 1 year ago.
just for future reference you can do the process even if light stays on? When you read it, it says 10 minutes or light goes out. I take that as which ever comes first?
Expert:  BOBBYSS replied 1 year ago.

Yes. I do it with a scan tool, but if I need to do it manually it is by the 10 minutes only.

Customer: replied 1 year ago.
I have a scan tool but not a tech 2
Expert:  BOBBYSS replied 1 year ago.

Then try the reset procedure I mentioned. If it does not work then the new PCM may not be communicating with the BCM.

Customer: replied 1 year ago.
its on second cycle now. PCM not communicating with BCM? Which will need what? BCM programmed?
Customer: replied 1 year ago.
Are there any tech 2 tools out there for the novice? I'm not wanting to spend 4k on a scan tool....
Expert:  BOBBYSS replied 1 year ago.

What was the vehicle doing which caused you to replace the PCM?

Customer: replied 1 year ago.
it was jerking while driving, was not the transmission because I would put it in neutral and it would hesitate. It was jerking too hard to be just a single misfire(in my novice opinion). Was not getting a check engine light. It would only do while driving. Fuel pressure good while sitting of course. I replaced fuel filter because it was cheap and those can be filter symptoms. My 300$ advanced auto scan tool showed no codes at all and no pending/old codes and no check. I took to a shop and pain 150 diagnostic fee. They said computer was shutting fuel pump on and off. I order used one from show who programmed to my vin. I put it in and here we are
Expert:  BOBBYSS replied 1 year ago.

Thank you. I have not seen a PCM cause this before. Let me know what happens after the reset.

Customer: replied 1 year ago.
nothing security light still on. I was wondering if it was something with the fuel pump or wiring because I notice my fuel gauge is off and has become even more off since the problem started. Sometimes it will move. But they said the pcm was causing the fuel pump to shut on and off. Said antitheft....
Customer: replied 1 year ago.
still wont start
Expert:  BOBBYSS replied 1 year ago.

Is the security light on while cranking the engine? Do you still have the old PCM?

Customer: replied 1 year ago.
I do have the old pcm. The engine does not crank but if I turn the key crank position the light goes out
Expert:  BOBBYSS replied 1 year ago.

If the light goes out then it should be registering the right key. If not the light would remain lit. Did you try putting the old PCM back in?

Customer: replied 1 year ago.
When I turn key in crank position all dash goes off. And I did put old back in. Still security light
Expert:  BOBBYSS replied 1 year ago.

If all of the lights go off when holding in the crank position then you may have another issue. You might have a failing ignition switch. Do you have a voltage meter to run through some tests?

Customer: replied 1 year ago.
I do. Now the fuel gauge is showing empty. Lol. That's new
Customer: replied 1 year ago.
Everything shuts down on dash in crank position except check engine
Expert:  BOBBYSS replied 1 year ago.

I would test the ignition switch. You need to remove the panels to be able to access the back of the switch while it is still connected. First test the power to the switch. Two of the wires should have power. Then install the key and turn it to the run position. You should have power at all but the yellow wire. Then with the key in the crank position the yellow wire should get power. If any of these do not make sense please let me know.