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Jay
Jay, Certified Infiniti Technician
Category: Infiniti
Satisfied Customers: 19057
Experience:  20+years, Nissan and Infiniti experience and currently now working for a Infiniti Dealer
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2004 Infiniti QX56 wont turn over, when the key is turned

Customer Question

2004 Infiniti QX56 wont turn over, when the key is turned nothing happens, replaced the battery (new), replaced the BCM module and Fuse Box Relay Unit Module (both used) Reset the anti theft by locking and unlocking doors with key. Jumped the starter remotely with a jumper wire. the engine will turn over but not start. Any ideas?
Submitted: 6 months ago.
Category: Infiniti
Expert:  Jay replied 6 months ago.

Hello my name is ***** ***** thank you for your question.

When you turn the key to the ON position, does all dash warning lights come on? Also do you happen to know if the truck has a after market alarm installed?

Customer: replied 6 months ago.
all the dash lights come on
No it does not have an aftermarket alarm
Expert:  Jay replied 6 months ago.

Do you have a test light? Also did you remove the plenum to expose the starter?

Customer: replied 6 months ago.
FYI i checked all the fuses all were goodYes i pulled the plenum (easier than i thought) removed the starter and had it checked, it checked out to be good.
Expert:  Jay replied 6 months ago.

oh boy.. You had it bench tested? does it signal click when you try to start the truck?

Customer: replied 6 months ago.
If you mean does the starter click? no it does not
When i turn the key there is no sound at allanother note when the key is inserted and the door is open there is no warning "ding"
Customer: replied 6 months ago.
i had the started bench tested
Expert:  Jay replied 6 months ago.

I hate bench tests. The reason being that they do not put a load on it. So it could pass a bench test, but not work still when installed. But lets move forward and see if we can verify the starter.

You said you have a test light right?

Customer: replied 6 months ago.
I mentioned i traced the wire to the fuse box next to battery and jumped it to the battery.the engine cranks just fine like it has before.
But will not start, thus i am certain it is not a starter problem
Expert:  Jay replied 6 months ago.

Ok.. Do you know if the start signal gets power when the key is turned to the crank position? Also can you read a wiring diagram?

Customer: replied 6 months ago.
When you ask about the start signal, do you mean at the ignition switch under the dash? If so i am not sure which wire to checkYes i can read a wiring diagram, its been a while but sure i can still navigate through them.
Expert:  Jay replied 6 months ago.

Give me a min please..

Customer: replied 6 months ago.
10-4
Expert:  Jay replied 6 months ago.

I am going to get you a Terminal out of the IPDM, so hang on. I want to see if you have power at pin 48 at the IPDM when the truck is in park or neutral. Hang on.

Customer: replied 6 months ago.
Do I check to see if the fuse marked as 48 has power on both sides of the fuse?
Expert:  Jay replied 6 months ago.

No.. Pin 48 in the IPDM. We want to see if that has power

Customer: replied 6 months ago.
I'm checking give me a minute
Expert:  Jay replied 6 months ago.

Sure.. Check with a volt meter if you can. I will wait.

Customer: replied 6 months ago.
power in both park and neutral with a test light
No power in drive or reverse
Checked with a test light I don't have a bolt meter with me
Expert:  Jay replied 6 months ago.

Now see if you have power at pin 19 with the key in the crank position

Customer: replied 6 months ago.
No power
White wire with red stripe
Same color wire I used to remote jump the starter that s located in a plug connection next to IDPM
Expert:  Jay replied 6 months ago.

How about pin 21.. Does that get power?

Customer: replied 6 months ago.
let me check
Expert:  Jay replied 6 months ago.

when the key is turned to the crank position?

Customer: replied 6 months ago.
on brown wire
Expert:  Jay replied 6 months ago.

Then you may have a bad IPDM. The start relay is built into it. The only other thing that could cause this is if the Transmission is not grounding the power from pin 48 at the trans to activate the coil side of the relay. Which would mean it's a internal transmission issue.

But I would try a IPDM first and if that doesn't change it, then you know your looking at a trans issue.

Do you have any more questions on this?

Customer: replied 6 months ago.
I just changed the IDPMWhat if i put a jumper wire to the 21 pin (brown wire) to the 19 pin (white wire with red stripe) will that bypass the starter relay in the IDPM?
Expert:  Jay replied 6 months ago.

It will by pass the relay, but that will allow the starter to be engaged with the truck in gear as well.

Expert:  Jay replied 6 months ago.

But if you are always aware of it being there and aware it can turn over while in gear and you are careful, you can do that.

Expert:  Jay replied 6 months ago.

Just keep in mind you are by passing the safety feature.

Customer: replied 6 months ago.
I understand
let me try this and see if it starts ill let you know the outcomeCan i resume this conversation at a latter time.I have to go to a wedding and i'm late
so ill have to try this tomorrow.
if so how do i restart the conversation?
Expert:  Jay replied 6 months ago.

To return you only need to log into JustAnswer.com and go to my questions. Your user name and password ***** have been emailed to you.

Expert:  Jay replied 6 months ago.

Enjoy your wedding!

Customer: replied 6 months ago.
It was a quick check so I tried it
The engine cranks with the key now
But does not fire and start
Give me something to check when I get back latter
Expert:  Jay replied 6 months ago.

see if the security light is ON solid when the key is turned to the ON position.

Also scan for codes.

Customer: replied 6 months ago.
I know from before that the red security light in the center of the dash next t the windshield is not ON at all no flashing no solidAnd I don't have a scanner let me know
Thanks for all your help thus far
Expert:  Jay replied 6 months ago.

Lets talk tomorrow. I know you need to go. I will be online

Customer: replied 6 months ago.
Jay,Can we continue with our diagnosis and repair of the Infiniti ?
Expert:  Jay replied 6 months ago.

Sure.. Give me 10 mins

Customer: replied 6 months ago.
OK
Expert:  Jay replied 6 months ago.

Ok.. Lets try to swap the Ecm Relay in the IPDM with the Fog light relay and see if the truck starts. Also if you are able to check for codes, let me know if there are any codes stored.

Here is a image of where the Relays are located in the IPDM. I made the ECM Green so you know which one it is.

Let me know how you make out.

https://dl.dropboxusercontent.com/u/105565483/Ecm%20Relay%20location%20in%20IPDM%202.jpg

Customer: replied 6 months ago.
I had already tried switching the relays, in fact i purchased two new relays and installed them.I tried again now, just to confirm.
Same result
still will not crank
Expert:  Jay replied 6 months ago.

Oh, we are back on the cranking? I thought we were trying to get it running?

Customer: replied 6 months ago.
Sure
I have no problem with having a jumper wire between the 21 pin (brown wire) to the 19 pin (white wire with red stripe)I just now tried that and the engine cranks but does not start
Expert:  Jay replied 6 months ago.

Do you know if you have any codes.. I have a feeling I may know what it is.

Customer: replied 6 months ago.
No,The truck quit running at our place of business, so i have not been willing to tow it to the dealer to run codesI don't have a scanner.What your feeling and lets try it
Expert:  Jay replied 6 months ago.

Well it's hard to try if it's something in the transmission. If you look at the wiring diagram, if the valve body in the transmission ( TCM - Transmission Control Module ) has failed, it won't ground the coil side of the start relay. At the same time, the truck won't start cause it doesn't see it's in the right shift position or can't communicate with the TCM to allow the truck to start.

Expert:  Jay replied 6 months ago.

We know the start relay is not getting activated, so we are most likely looking at a Transmission valve body issue I am afraid.

Expert:  Jay replied 6 months ago.

If you have any more questions on this, please feel free to ask.

If not, and you're satisfied with my help, please Rate me. That is how I get credit for my work. I hope I have provided you with Excellent Service.

Thanks Jay!

Customer: replied 6 months ago.
I know my way around transmissions i owned an AAmoc Transmission Shop for six yearsDo you have a wiring diagram for the transmission as well as a drawing for the vale body that shows which relay we are taking about?It should be easy to ground the wire leading out of the relay in the transmission. By doing this and the truck starts, this will verify the problemLet me know what you have
Customer: replied 6 months ago.
AAmco Transmission Shop
Expert:  Jay replied 6 months ago.

These valve bodies are not like the older ones. The TCM control unit is built into the valve body, so it would require the valve body to be replaced.

Expert:  Jay replied 6 months ago.

It is not something you can repair in the valve body since it is computer controlled.

Expert:  Jay replied 6 months ago.

The ones I have seen cause this doesn't even throw a code. I would simply see if pin 9 at the transmission goes to ground or stays hot.. That is how you would verify it's in the valve body

Customer: replied 6 months ago.
do you have a drawing that will show me which is pin 9 at the transmission?when should the pin turn to ground ? When the key is turned to crank?
Expert:  Jay replied 6 months ago.

If you have any more questions on this, please feel free to ask.

If not, and you're satisfied with my help, please Rate me. That is how I get credit for my work. I hope I have provided you with Excellent Service.

Thanks Jay!

Customer: replied 6 months ago.
i still have questions,thanks for the drawings but i still don't know where to find pin 9 ?i didn't get an answer regarding when should the pin turn to ground ? When the key is turned to crank?I would Love to get you paid and give you an excellent rating, but we still have not identified the problem for sure.I don't have a problem changing the vale body but only if we are certain that is the issue and will correct the problem
Expert:  Jay replied 6 months ago.

pin 9 will ground when it can determine the truck is in Park / Neutral. pin 9 is on the transmission

Expert:  Jay replied 6 months ago.

You said you were getting power at pin 48 in the IPDM when the truck was in park or neutral correct?

Customer: replied 6 months ago.
power at pin 48 in both park and neutral with a test light
No power in drive or reverse
Expert:  Jay replied 6 months ago.

If that is the case, it's very possible there is a issue internally with the IPDM. The we verified the relay is not activating. But we need to figure out if it's because the Trans is not grounding the coil side of the relay, or if the relay it's self is bad.

Expert:  Jay replied 6 months ago.

https://dl.dropboxusercontent.com/u/105565483/Pages%20from%20PG.pdf

That is the IPDM layout. May want to swap that relay with the fog light relay and see if the engine turns over using the key with out the jumper.

Customer: replied 6 months ago.
I replaced the IPDM,
It was a used one and not inconceivable that it could be bad, but having two bad units with the same issue?I switched the fog lamp relay with the ECM alreadywhich other relay should i switch the starter or Ignition relay or both
Expert:  Jay replied 6 months ago.

They changed these IPDM's to a Black case verses the white. Since the White ones like in the first picture with the Ecm relay location they don't make any more. But if your having the exact same issue with the new ( used ) IPDM as the last one where the starter relay is not engaging, then it's in the transmission the problem

Customer: replied 6 months ago.
I have access to a new TCM and used valve body that i can take apart and clean.that will take me a few days.ill get back to you and let you know.i am going to see about the ground on pin 9 before i pull the valve body
Expert:  Jay replied 6 months ago.

ok

Customer: replied 6 months ago.
question?
once i identify pin 9 on the trannyIf i cut the wire going to the IDPM and ground it to the frame, and the truck cranks and starts that should confirm a bad TCM, correct?I understand that this will not correct the problem but should confirm. Will still need to replace the TCM as it controls other things.Whats your thoughts?
Expert:  Jay replied 6 months ago.

The way I am seeing your issue, first we don't have a way to check for codes. That would really be the first thing you should do. Codes are the most important thing to check for no start issues or any type of issue your having. If you have a Bad TCM, that will keep the truck from starting and can also keep the starter relay from engaging. So simply grounding Pin 9 or Pin 48 will only allow the starter to engage. The control units still talk to each other through the CAN line. So if the TCM is not responding or not communicating, that would also keep the truck from starting when you jump that relay

Customer: replied 6 months ago.
Jay,I obtained a scanner
These are the codes it gives me
P0462, P0465, P0725, P1065, P1212, P1610, P1612, P1705, U1000, U1001 & U1065
Customer: replied 6 months ago.
What can you help me with with these codes?i'll be around all day tomorrowThanks
Robert
Expert:  Jay replied 6 months ago.

When I look at those codes. The first thing you need to fix is the U1000 and U1001 codes. That is a indication of control unit failure. This will require a advanced level scanner to do what they call a CAN system check to see what control unit is not communicating. See image for example of a CAN diagnostic system chart.

https://dl.dropboxusercontent.com/u/105565483/CAN%20Image.jpg