2006 No start/no security light (injector/fuel pump kill?) - Chevy Impala Forums
Chevy Impala Discussion Discuss all non-technical general Chevy Impala topics here.

User Tag List

 1Likes
  • 1 Post By ironstone
 
LinkBack Thread Tools Display Modes
post #1 of (permalink) Old 08-11-2019 Thread Starter
Junior Member
 
ironstone's Avatar
 
Join Date: Aug 2019
Posts: 6
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 6 Post(s)
Thanks: 2
Thanked 0 Times in 0 Posts
2006 No start/no security light (injector/fuel pump kill?)

My sister-in-law has a 2006 that's not sending power to the solenoid when you attempt to start it. The fuel pump does engage when the ignition is first unlocked and pressurizes the line.


Providing power to the solenoid directly with the key in the run position cranks the engine and it will run briefly (approx 5 seconds) and then stalls out as if its no longer getting fuel.


There's a leak in the firewall and I expect its related to corrosion/water damage in the dash but I'm not finding troubleshooting for these specific symptoms.



I'd prefer to be more proactive than trying to replace every possible component until I find the culprit given that a doing so would exceed the value of the vehicle when considering parts and time/effort especially since I'm unfamiliar with this particular vehicle and the haynes manual is a crapshoot in terms of accuracy.


Does any one have suggestions or sources for troubleshooting or wiring diagrams?



Thanks in advance!
ironstone is offline  
Sponsored Links
Advertisement
 
post #2 of (permalink) Old 08-11-2019
Senior Member
 
plano-doug's Avatar
 
Join Date: Aug 2009
Location: Plano, Texas
Posts: 2,597
Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 378 Post(s)
Thanks: 130
Thanked 374 Times in 349 Posts
Quote:
Originally Posted by ironstone View Post
My sister-in-law has a 2006 that's not sending power to the solenoid when you attempt to start it. The fuel pump does engage when the ignition is first unlocked and pressurizes the line.

Providing power to the solenoid directly with the key in the run position cranks the engine and it will run briefly (approx 5 seconds) and then stalls out as if its no longer getting fuel.

There's a leak in the firewall and I expect its related to corrosion/water damage in the dash but I'm not finding troubleshooting for these specific symptoms.

I'd prefer to be more proactive than trying to replace every possible component until I find the culprit given that a doing so would exceed the value of the vehicle when considering parts and time/effort especially since I'm unfamiliar with this particular vehicle and the haynes manual is a crapshoot in terms of accuracy.

Does any one have suggestions or sources for troubleshooting or wiring diagrams?
It sounds like you may have 2 different problems. I'd start with the no-crank situation. Does the starter relay click when the key is turned to CRANK? It's in the underhood fuse box. If the relay doesn't click, you'll need to check the wiring from the fuse box back to the starter switch. If the relay is clicking, then you need to check continuity from the relay to the starter solenoid. Another test you can do here is to swap a different relay in for the starter relay. This will help reveal if you have a bad starter relay or something else.

I would try to get the no-crank situation resolved first, then focus on the dying problem. My first guess on that is a bad fuel pressure regulator. Which engine does this car have?

HTH.

Doug

.

Last edited by plano-doug; 08-11-2019 at 05:54 PM.
plano-doug is offline  
post #3 of (permalink) Old 08-11-2019 Thread Starter
Junior Member
 
ironstone's Avatar
 
Join Date: Aug 2019
Posts: 6
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 6 Post(s)
Thanks: 2
Thanked 0 Times in 0 Posts
Shes had issues with the security system in the past and I suspect this is more of the same. I think its a 3.9 liter but will have to check.

You can hear relays engage when the key is turned to run then a other when continuing to the start position.

Im trying to find information on how to sort out security system issues from other electrical issues without teariing the whole dash apart and crawling around with a volt meter.

The more i read up on this car the more i suspect its something with the bcm and or pcm.
ironstone is offline  
Sponsored Links
Advertisement
 
post #4 of (permalink) Old 08-12-2019
Senior Member
 
plano-doug's Avatar
 
Join Date: Aug 2009
Location: Plano, Texas
Posts: 2,597
Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 378 Post(s)
Thanks: 130
Thanked 374 Times in 349 Posts
Quote:
Originally Posted by ironstone View Post
Shes had issues with the security system in the past and I suspect this is more of the same. I think its a 3.9 liter but will have to check.

You can hear relays engage when the key is turned to run then a other when continuing to the start position.

Im trying to find information on how to sort out security system issues from other electrical issues without teariing the whole dash apart and crawling around with a volt meter.

The more i read up on this car the more i suspect its something with the bcm and or pcm.
Can you describe the security problems from the past and how they were resolved? The earlier 2000-2005 Impalas were known for security issues, but it's not so common with the newer cars.

Is the SECURITY message flashing on the instrument panel during the no-crank condition?

As for relays, when the key is turned to START (CRANK) you want to be sure you can feel the starter relay clicking and not something else. Keep in mind, when the ignition switch is turned to START, it cuts off power to some circuits so that more current is available for the starter. So some of the clicking you hear could be relays for those other circuits, and not the starter relay.

Doug

.
plano-doug is offline  
post #5 of (permalink) Old 08-26-2019 Thread Starter
Junior Member
 
ironstone's Avatar
 
Join Date: Aug 2019
Posts: 6
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 6 Post(s)
Thanks: 2
Thanked 0 Times in 0 Posts
Quote:
Originally Posted by plano-doug View Post
Can you describe the security problems from the past and how they were resolved? The earlier 2000-2005 Impalas were known for security issues, but it's not so common with the newer cars.

Is the SECURITY message flashing on the instrument panel during the no-crank condition?

As for relays, when the key is turned to START (CRANK) you want to be sure you can feel the starter relay clicking and not something else. Keep in mind, when the ignition switch is turned to START, it cuts off power to some circuits so that more current is available for the starter. So some of the clicking you hear could be relays for those other circuits, and not the starter relay.

Doug

.
The car has a leak in the firewall. When parked uphill at all and it rains, they have to shop vac standing water out of the passenger side of the floor pan.

In the past, its just refused to take the key, it would do the typical flash security when attempting to crank. "Fixing" it was her waiting for 15 minutes and trying again.
'
About six months ago the ignition lock packed it in and froze up. Had to tow it home and my brother and I pulled the dash apart and replaced the cylinder (just the lock with its embedded sensor, not the ignition switch). It's behaved since in terms of the SECURITY light tripping.

Between work, weather and other commitments I haven't had a chance to crawl back under the hood/dash yet.

I'd almost buy a bad ignition switch except for the fact that the pump engages at the run position until the line is pressurized then stops. If it can read the switch as on without the engine running, i'd expect it to read it as on with the engine running. The engine will run until the fuel pressure in the line drops then it starves out and dies.

Further reading makes me think that the signal the BCM is supposed to be sending to the PCM isn't making it there because its the same symptoms as a false security system lockdown without the security light flashing.

Whether that's from a bad/corroded connector or the BCM itself corroding/shorting out somehow due to the constant moisture remains to be seen.

I've managed to lay hands on a wiring schematic for the beast, so I'll probably start fault tracing from component to component when my schedule and the weather permits.

If the BCM has gone south, it'll probably end up in the salvage yard as my brother is seriously over this car.
ironstone is offline  
post #6 of (permalink) Old 08-26-2019
Senior Member
 
plano-doug's Avatar
 
Join Date: Aug 2009
Location: Plano, Texas
Posts: 2,597
Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 378 Post(s)
Thanks: 130
Thanked 374 Times in 349 Posts
Quote:
Originally Posted by ironstone View Post
The car has a leak in the firewall. When parked uphill at all and it rains, they have to shop vac standing water out of the passenger side of the floor pan.
There's a piece under the cowling on the passenger side that may have become dislodged. With the wiper(s) removed, you can lift the grate off and reposition the piece. That may cure the leaking.

Quote:
In the past, its just refused to take the key, it would do the typical flash security when attempting to crank. "Fixing" it was her waiting for 15 minutes and trying again.
That's in line with the typical security problem. A few pins in the connector at the BCM develop too much resistance causing the BCM to mis-read the "key detector". I believe the key detector is a hall-effect sensor, which detects the presence of metal. Regardless of the technology, if it's not working correctly, the SECURITY condition occurs and the car won't crank.

There's a TSB on this that I don't have handy. But the fix is to clean the connector contacts simply by disconnecting and reconnecting the BCM connectors a few times (with the battery disconnected!). The BCM is over the driver's left foot, and has three connectors with pinch handles. Pinch one and slide it out, then re-insert it. Do that 2 or 3 times, to each of the 3 connectors. That should fix any lingering SECURITY issue.

There is also a bypass that some folks would do wherein they put a resistor between two of the 3 wires going to the key detector. The details escape me, but they're searchable on the forum.

I attribute the increasing resistance to galvanic corrosion. As I understand it, if the metal platings on the connector pins are not perfectly compatible, the corrosion can form causing the mis-read of the key detector.

Quote:
About six months ago the ignition lock packed it in and froze up. Had to tow it home and my brother and I pulled the dash apart and replaced the cylinder (just the lock with its embedded sensor, not the ignition switch). It's behaved since in terms of the SECURITY light tripping.
As I recall, the key detector inserts into the side of the lock cylinder above the switch portion. If you are still getting the SECURITY, I would inspect the cylinder to be sure the detector is still in place.

All that said, re-reading your post, you have a 2006. The SECURITY issue was mostly confined to the 2000-2005 models.

Quote:
I'd almost buy a bad ignition switch except for the fact that the pump engages at the run position until the line is pressurized then stops. If it can read the switch as on without the engine running, i'd expect it to read it as on with the engine running. The engine will run until the fuel pressure in the line drops then it starves out and dies.
Once pressure it built up, the fuel pump is supposed to shut off on this model. I suggest getting a fuel pressure gauge and hooking it up to the fuel rail in the intake and watching it to see exactly what it's doing. IIRC, it should be close to 50 psi.

HTH.

[Edit]Looking at my manual, there is a fuel pressure regulator for this motor. If yours has gone bad, it may be letting the pressure drop too low for the injectors. Again, the fuel pressure gauge can help verify that. If you have to replace it, unlike the previous generation of Impalas where it's under the hood, for the 2006 3.9, the regulator is part of the fuel sending unit in the tank, so the tank has be dropped to service it.

Doug

.

Last edited by plano-doug; 08-26-2019 at 04:28 PM.
plano-doug is offline  
post #7 of (permalink) Old 08-26-2019 Thread Starter
Junior Member
 
ironstone's Avatar
 
Join Date: Aug 2019
Posts: 6
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 6 Post(s)
Thanks: 2
Thanked 0 Times in 0 Posts
Quote:
Originally Posted by plano-doug View Post
Can you describe the security problems from the past and how they were resolved? The earlier 2000-2005 Impalas were known for security issues, but it's not so common with the newer cars.

(snip)

Doug

.

And I stand corrected, its actually a 2005.
plano-doug likes this.
ironstone is offline  
post #8 of (permalink) Old 08-26-2019
Senior Member
 
plano-doug's Avatar
 
Join Date: Aug 2009
Location: Plano, Texas
Posts: 2,597
Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 378 Post(s)
Thanks: 130
Thanked 374 Times in 349 Posts
Quote:
Originally Posted by ironstone View Post
And I stand corrected, its actually a 2005.
That's good to know. Things may have just gotten easier (at least, easier for me ).

Can you verify which engine you have?

The 2000-2005 cars have a port behind the rear seat allowing easy access to the fuel pump, should that be necessary. (No need to drop the tank.) Also, on these there's a fuel filter under the driver's seat, which could be contributing to the problem.

Doug

.
plano-doug is offline  
post #9 of (permalink) Old 08-26-2019 Thread Starter
Junior Member
 
ironstone's Avatar
 
Join Date: Aug 2019
Posts: 6
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 6 Post(s)
Thanks: 2
Thanked 0 Times in 0 Posts
Its the 2005, 3.4 liter, base model sedan. Showed my brother the wiring diagram this evening and he pointed out my mistake on the year. (facepalm).

The fuel pressure gauge is a great idea and I'm going to give that a shot to see exactly what its doing in terms of pressure. Assuming it shows the proper pressure when it first initializes the pump, I may tap into the fuel pump power wire to confirm if the pump is being engaged at all after the initial pressurization of the line.

Question: If the fuel pressure is normal prior to starting the engine, but the pump does not re-engage when the pressure drops, is that still a symptom of a bad pressure sensor? I'd think if its reading the pressure accurately when in RUN prior to engine start, it should read it as well when the engine is drawing fuel.


We're not getting the flashing security warning like had happened in the past before replacing the bad lock cylinder.

Correct me if I'm wrong, but as I understand the way the lock out functions is the sensor verifies the key providing an expected resistance to the BCM. If the BCM detects the expected resistance it sends a specific signal to the PCM to enable power to the starter and fuel pump.

If the resistance is wrong, the BCM triggers the security light to flash, and refuses to send the "all clear" signal to the PCM.

My theory is that the resistance from the lock sensor is being accepted but the signal is failing to be recieved by the PCM due to faulty wiring or horrors of horrors a BCM that is not functioning as it should. I suppose the PCM could be having its own issues, but i'm under the impression that its under the hood and not likely be be involved with the firewall leak thats been ongoing.

I really wish I could find out what signal form is being sent to the PCM to engage so I could spoof the signal and narrow down which component is actually failing without having to play the buy and replace everything until it works or I give up due to the increasing costs.

Thanks again Doug for all the suggestions. I'll keep you updated as I rule things out and what it was if I get it running.

Last edited by ironstone; 08-26-2019 at 07:26 PM.
ironstone is offline  
post #10 of (permalink) Old 08-26-2019
Senior Member
 
plano-doug's Avatar
 
Join Date: Aug 2009
Location: Plano, Texas
Posts: 2,597
Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 378 Post(s)
Thanks: 130
Thanked 374 Times in 349 Posts
Quote:
Originally Posted by ironstone View Post
Its the 2005, 3.4 liter, base model sedan. Showed my brother the wiring diagram this evening and he pointed out my mistake on the year. (facepalm).
I have had two Impalas with the 3.4. As I recall, your symptoms are much like those of a failing fuel pressure regulator. The car starts, but won't stay running. You can test it by borrowing a fuel pressure gauge from a parts store, and connecting it to the schrader valve at the end of the fuel rail on the passenger end of the motor. With engine off/key on, the fuel pressure should be in the range 52-59 psi. With the engine running at idle (assuming it cranks and fires), it should drop 3-10 psi.

The regulator sits at the end of the fuel path, on the front bank of the motor, driver's end, near the throttle body. You'll need a torx tool to get it out. Not sure that else - it's been too long since I last did one.

HTH.

Doug

.
plano-doug is offline  
The Following 2 Users Say Thank You to plano-doug For This Useful Post:
ironstone (08-26-2019)
post #11 of (permalink) Old 08-26-2019 Thread Starter
Junior Member
 
ironstone's Avatar
 
Join Date: Aug 2019
Posts: 6
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 6 Post(s)
Thanks: 2
Thanked 0 Times in 0 Posts
The car starts if you provide twelve volts to the solenoid while the igniton is in the run position. The wire that normally powers the solenoid does not show any voltage when turning the ignition to start. Its this conjunction of lack of fuel and lack of crank that has me looking at the BCM/PCN communication as the probable issue as this is exactly what it does when the security mode is triggered.
ironstone is offline  
post #12 of (permalink) Old 08-27-2019
Senior Member
 
plano-doug's Avatar
 
Join Date: Aug 2009
Location: Plano, Texas
Posts: 2,597
Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 378 Post(s)
Thanks: 130
Thanked 374 Times in 349 Posts
Quote:
Originally Posted by ironstone View Post
The car starts if you provide twelve volts to the solenoid while the igniton is in the run position. The wire that normally powers the solenoid does not show any voltage when turning the ignition to start. Its this conjunction of lack of fuel and lack of crank that has me looking at the BCM/PCN communication as the probable issue as this is exactly what it does when the security mode is triggered.
I've attached a drawing for the starting circuit. To be clear, you are getting the no-crank condition, but the SECURITY light is NOT flashing, correct?

If that's the case, I would trace out the starting circuit. Make sure you see the CRANK signal go high at the PCM when the key is turned. Verify the fuse in that path is good. Verify the signal between PCM and starter relay in the underhood fuse box. Verify continuity between that relay and the starter solenoid. In short, you need to figure out where the break down is in that path.

Once you get it cranking reliably, then shift focus to idling/dying.

When you do continuity checks (ie, measuring ohms between the ends of a wire) I recommend having the battery disconnected.

HTH.

Doug

.
Attached Thumbnails
Click image for larger version

Name:	2005_impala_starting_schematic.png
Views:	15
Size:	59.5 KB
ID:	146075  

Last edited by plano-doug; 08-27-2019 at 08:07 AM.
plano-doug is offline  
Sponsored Links
Advertisement
 
Reply


Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Chevy Impala Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome