Cranks no start

Are you certain there is no spark? Have you scanned the computer to see if there are diagnostic trouble codes? I ask about the spark because if you already replaced the crankshaft position sensor, either there is a wiring issue or something with the PCM.

The PCM uses the crankshaft position signal to calculate a spark target and then fires the coil pack.

Interestingly, the coils always have power to them. The PCM provides a ground path to initiate spark. If you look at the pic below, check the PCM fuse and relay. Let me know what you find. Also, check to make sure there is power to the red wires at each coil.

Joe

I think you are referring to the 30 amp fuse listed in the pic above.

Troy, you have power from the PCM if the red coil wires have power. If you look at the attached pic (sorry for the 1st grade hand writing) I circled the red wire that goes to the PCM. That is the supply for the coils.

However, if we have power, we need a ground to fire the coils. In the pic I highlighted each wire that goes to the PCM for ground. That ground path only opens when the PCM knows it's time for a coil to fire. You need to check if there is continuity to ground at those wires when the engine is being cranked. If there isn't, go back to the PCM and inspect to make sure everything is tight and not damaged.

If everything is good you need to check right at the PCM to see if there is a ground path when cranking the engine. If there isn't, the PCM has failed or has lost ground. See pic 2 for ground location. Also, note there is a splice in that ground, so when checking for continuity, take into consideration the splice may have failed.

Now, do not disconnect or re-connect the PCM with the battery connected. Always disconnect the battery before doing either.

Let me know.
Joe

Hi,
No, I don't see how the remote would cause this unless it is an aftermarket set up.

As far as the spark issue, if you have a ground path to the PCM from each coil when cranking and there is power to the coils, that makes no sense. They all couldn't have gone bad at the same time.

When you checked ground, was it a pulse like signal you got? Also, do you have access to a live data scan tool? I would love to know if there is an RPM signal when cranking.

Let me know.
Joe

Hi,

This is everything I have as far as the battery junction box and the central junction box. The last pic below shows where the first pic I sent you is located.

Let me know if this helps.

Joe

Hi,

The keep alive can be set if the battery was disconnected or if voltage fell below 10.4v. There is a chance the PCM is bad, but that is not the usual cause. If the PCM is bad, then yes it can cause a no start.

Joe

Hi,

Troy, good to hear from you. I have to ask a favor. Is it possible for you to copy and paste the Nissan question to a new post? We are trying to keep everything specific to one topic.

Here is the link:

https://www.2carpros.com/questions/new

I hope you understand. I will watch for your post.

Take care,
Joe

Hi,

If you use the key to unlick the door, it should turn the immobilizer off. Have you tried to scan the CAN BUS system to see if there are any codes related to the immobilizer? For example, a P1260.

Also, did he retrieve the vehicle identification info prior to removing the old PCM?

Here are the directions when replacing / reprogramming one. Let me know if this is what he did.

_____________________

1999 Ford Mustang Cobra V8-4.6L DOHC VIN V
Reprogramming
Vehicle Powertrain Management Relays and Modules - Powertrain Management Relays and Modules - Computers and Control Systems Engine Control Module Service and Repair Procedures Reprogramming
REPROGRAMMING
Flash Electrically Erasable Programmable Read Only Memory is contained in an Integrated Circuit (IC) internally to the PCM. The EEPROM contains the vehicle strategy as well as any calibration information specific to the vehicle.

The IC is reprogrammable and at times it may become necessary to reprogram or reflash the entire contents. This is usually due to either an after production strategy change or the Vehicle Identification (VID) area has been previously reprogrammed and has reached its limit. The VID block area can be tailored to accommodate various hardware changes made to the vehicle since production. The VID block is a section of memory within the IC which includes items such as octane adjust, fuel octane, fuel type, tire size and axle ratio.

Pic 1

Programming a Replacement PCM
A replacement PCM will display a label as shown. This indicates the need to retrieve VID data from the original PCM before removing from the vehicle. Refer to the flash VID block update procedure. After retrieving the VID data from the original PCM, install the new PCM. Select "Restore PCM config. (1)" to download the stored data. If the original PCM is nonfunctional, it becomes necessary to manually reprogram the VID block. The scan tool is used to perform this procedure and is done through the "PCM Programming" selection as described by the flash EEPROM procedure below. Follow screen instructions.

Flash EEPROM Procedure
When using the NGS to reprogram the entire IC contents, the NGS Flash kit will be used. The Service Bay Technical System (SBTS) is used to download the new strategy with calibration onto the NGS static RAM card (data transfer card). The card is part of the flash kit. Plug the NGS flash cable into the under dash OBD II connector. Follow the NGS screen instructions under "PCM Programming" or refer to the flash instruction manual provided in the kit. VID block information can also be viewed and changed during this procedure.

Flash VID Block Procedure
When using the NGS scan tool, the Ford Service Function (FSF) card is used along with the NGS flash cable. Plug the cable into the under dash OBD II connector. From the main menu, select "Service Bay Functions", "PCM-Powertrain Control Module" and then "Programmable Module Installation". The screen will now display two selections. The first is for old PCM information to be retrieved and stored within the NGS. The second is for restoring the new PCM with information which has been retrieved from the old PCM. Follow screen instructions or refer to the supplement instruction sheet included with the Ford Service Function card. Next, either a transfer of data from the old module to the new module or a manual update must be performed on the VID block. Follow screen instructions or refer to the supplement instruction sheet included with the Ford Service Function card. If the VID block has been reprogrammed previously, the scan tool will display a message. This message will indicate the need to reflash the entire IC.

NOTE: If using a generic scan tool, follow the instruction manual provided by the tool manufacturer.

Let me know.
Joe