Jump to content
HybridZ

Help.. Can't start my Ls1


Recommended Posts

Hi guys,

I am using a 1998 C5 PCM for my LS1 swap. I got Jesse from Wait4Me Performance to flash my PCM to remove the VATS. However my car will run for a short second then shuts off. At one time it ran for like 3 seconds and then shut off. I think the PCM is shutting the fuel and ignition off due to missing signals from other control modules. Anyone got away with using the C5 PCM in your swap? I have a fuel pressure gauge hooked up and the pressure was good. I have all the sensors hooked up except for the O2 sensors. I've read the C5 service manual and it said that the PCM needs to receive some signals from other control modules thru the serial lines in order to keep the car running. Anyone has any idea what's happening? Please help. Thanks in advance.

V.

PS. I will have to call Jesse on Monday to check. I did mentioned to him that I am using the C5 PCM.

Link to comment
Share on other sites

Yeah that's what I am thinking too. If I can find someone close by with a running PCM I can try out then I can make some complaint to Jesse. If not how else can I prove it to him?

 

I got all the grounds behind the block connected. I will double check the connectors to the CPS and the MAP sensor. I thought these 2 sensors (in the back of the engine) have different plugs. It's sucks that I have to wait til Monday to contact Jesse. Thanks for the response.

Link to comment
Share on other sites

Mike,

I just check the wires for the 2 sensors you mentioned above. Can you tell me the color wires that go to the MAP and the CPS. The MAP sensor is the one on top and the CPS is at the bottom. I check the wire to these sensors and even if I want to hook it up wrong I can't because of the wire length. The wire to the MAP sensor won't reach CPS but I just want to make sure. Also if the 2 plugs were wrong the car shouldn't run at all right? Thanks for your help.

Link to comment
Share on other sites

Hi Dale,

Can you tell me the color wires that go to the MAP sensor? I checked the display on the instrument cluster and it says "Reduce Engine Power". I talked to Jesse and he said he did disabled the VATS system and the car should start up. I talked to another friend of mine and he said sound like he didn't disable the PASS-key system. I thought the PASS-key integrated into the VATS system. Can someone verify this? Anyway I am waiting for my nephew to return my code reader so I can read the code off the PCM. That should tell me what's missing or what's wrong.

Link to comment
Share on other sites

Just found out something too. The C5 has something call PASS-key which works like another VATs system. That will cut out the fuel also. I am looking at a picture of the original wiring harness and I am sure that I didn't cross the wires for the MAP and CPS. Will read the code tonight when I get home

Link to comment
Share on other sites

He said I hooked up something wrong. Right the way I know that is BS. I used the whole C5 wiring harness completely hooked up the under hood fuse box. From the fuse box there are a few big wires going straight thru the ignition. All I did was splice in the power wires from the Z's ignition to the fuse box. Anyway Jesse told me to get a code reader to get the code off the PCM. Since I am using the C5's instrument cluster I can use it to get the code. I just got the procedure "how to read the code" off the Corvette forum. Will let you guys know what I find tonight.

Link to comment
Share on other sites

Guys,

I've been posting in the LS1tech forum too and receive no help. I guess no one ever completed the C5 LS1 swap into another car yet. Anyway I read the code off the car thru the instrument pannel cluster. I have no codes for the PCM and the IPC. However I have "no comm" with the BCM. I should have known about the PCM. I've read my friend's C5 manuals awhile back and I knew I will need the BCM to get the car started. However when I decided to send the PCM in for reprogramming I thought I didn't need it. So I cut it out. The good thing is I still have it. So tomorrow I will get the wiring info off my friend's manual and rewire it back in. I will update all the info on my page once I get it running. Anyway I found the section in the manual that mentioned about the BCM. I will post it here for you all to read.

 

Later.

 

PASS-Key Programming

The service BCMs EEPROM chip must be programmed with the proper RPO configurations by using a scan tool. The EEPROM stores information regarding the vehicle options and point of sale. If the BCM is not properly configured with the correct RPO codes, the BCM will set default values for some systems, which could cause malfunctions in other systems. When the BCM is replaced, the BCM must be programed to identify the following information:

 

Real Time Damping (RTD)

Memory Options

Daytime Running Lamps (DRL)

Front Fog Lamps

Tire Pressure Monitor (TPM)

HVAC (C60-Manual, CJ2-Automatic)

Country of Sale (US, Canada, Europe, Japan, etc.)

The BCM sends password information to the PCM on the serial data line to enable fuel for Content Theft Deterrent (CTD) functions, therefore, the PCM must also be programmed to accept the new password sent by the BCM. The BCM programming procedure will enable the learn password mode for both the BCM and PCM. This mode allows the PCM to learn the new password sent by the BCM whenever the BCM or PCM is replaced. If the BCM and PCM is not properly programmed together, the vehicle will exhibit a no start condition and the PCM will store a DTC P1631.

 

When an ignition key or the BCM is replaced, the BCM must be programmed to accept the resistance value of the new or existing vehicle keys in order to allow PASS-Key® operation. When the BCM is replaced, the service replacement BCM is programmed to accept the first PASS-Key® resistance value detected. If the BCM is unable to detect a valid PASS-Key® resistance value, the BCM will never end the programming sequence and a DTC B2735 will set. The BCM can also be programmed to accept a new PASS-Key® code by completing the following BCM/PASS-Key® programming procedure:

 

 

Important:

Before proceeding with this programming procedure, check for proper communications between the BCM and PCM. If communications cannot be established, refer to the appropriate Diagnostic System Check for the system unable to communicate.

 

Maintain the battery voltage while the PCM is in the Auto Learn Procedure. Follow this procedure exactly as indicated or you will have to repeat the procedure from the beginning.

 

 

Manual Programming (Domestic/Canada Only)

Using a Tech 2, select New BCM Setup and program the BCM with the correct RPO code configuration.

Turn ON the ignition leaving the engine OFF for 11 minutes.

Turn OFF the ignition for 30 seconds.

Turn ON the ignition leaving the engine OFF for 11 minutes.

Turn OFF the ignition for 30 seconds.

Turn ON the ignition leaving the engine OFF for 11 minutes or until DTC P1630 sets.

Turn OFF the ignition for 30 seconds.

Turn ON the ignition leaving the engine OFF and wait 30 seconds.

Attempt to start the engine. If the engine does not start, Refer to the Powertrain On Board Diagnostic (OBD) System Check in Engine Controls.

 

Important

Performing this procedure may cause a DTC P1630 to set. If a DTC P1630 sets, turn OFF the ignition for 30 seconds, then turn ON the ignition. If the DTC P1630 does not clear, Refer to Powertrain On Board Diagnostic (OBD) System Check in Engine Controls.

 

 

Tech 2 to Techline Terminal

Using a Tech 2, select New BCM Setup and program the BCM with the correct RPO code configuration.

Enter the Service Programming System (SPS) using a Tech 2.

Enter the vehicle information.

Choose the Request Info soft key on the Tech 2.

Select Done.

Follow the instructions on the Vehicle Set-up screen.

Disconnect the Tech 2 from the vehicle.

Connect the Tech 2 to the Techline terminal.

At the Techline terminal select Service Programming System (SPS) and select terminal to Tech 2 programming method.

Select Done.

Follow the instructions on the remaining screens.

Select the Vehicle Theft Re-learn option.

Select Program at the summary screen. The terminal will download information to the Tech 2.

Return the Tech 2 to the vehicle.

Connect the Tech 2 to Diagnostic Link Connector (DLC).

Select Service Programming from the Tech 2 main menu.

Answer the prompts regarding the model year and vehicle type.

Press the Theft Re-learn soft key on the Tech 2.

Follow the instructions on the remaining screens.

Attempt to start the engine. If the engine does not start, Refer to the Powertrain On Board Diagnostic (OBD) System Check in Engine Controls.

 

Important

Performing this procedure may cause a DTC P1630 to set. If a DTC P1630 sets, turn OFF the ignition for 30 seconds, then turn ON the ignition and P1630 clears. If the DTC P1630 does not clear, Refer to Powertrain On Board Diagnostic (OBD) System Check in Engine Controls.

 

 

Techline Terminal to Vehicle (No Tech 2)

Using a Tech 2, select New BCM Setup and program the BCM with the correct RPO code configuration.

Enter the Service Programming System (SPS) using a Techline Terminal (T-50/T-60).

Select terminal to vehicle programming.

Select Done.

Follow the instructions on the Vehicle Set-up screen.

Select the Vehicle Theft Re-learn option.

Follow the instructions on the remaining screens.

Attempt to start the engine. If the engine does not start, Refer to the Powertrain On Board Diagnostic (OBD) System Check in Engine Controls.

 

Important

Performing this procedure may cause a DTC P1630 to set. If a DTC P1630 sets, turn OFF the ignition for 30 seconds, then turn ON the ignition. If the DTC P1630 does not clear, Refer to Powertrain On Board Diagnostic (OBD) System Check in Engine Controls.

Link to comment
Share on other sites

If you have to you could have a new harness made that supports the newer computers. I have an extra 99 computer that I programed as a backup for mine that I would let you borrow if you go that route. Unfortunatly the 98 harness wont work with the 99 on up stuff because the pinouts are different.

 

Mine has no BCM, EGR, AIR, rear O2's or any other emission related stuff on it and it was a snap to hook up (got it from Speartech).

 

By the way, are you running the fly by wire Throttle body?

Link to comment
Share on other sites

Dale,

Yes I used the DBW from the C5 also. I also talked to John at Speartech and he said I basically on my own on this one. If I want to modify my harness and use a cable to the TB then I can use another PCM. I've made some progress tonight and got it to run 3 to 4 seconds now hehe. I am still missing a couple more things that I just found out when looking at the manuals. I will fix it tomorrow and give it another try. I am not giving up just yet hehe..

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...