2005 LR3 Dies While Driving
#31
09-18-2012, 07:51 AM
#32
09-18-2012, 09:07 AM
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No, the flashers didn't go on and I didn't notice the doors unlocking but then again I wasn't looking. I think the fuel cuts off because I have to give it a few turns of the key to start it. Impact sensor would be my thought. I located them and I'll give them a jiggle tomorrow because I'm at work today. There seems to be three. One severity sensor which is located behind the headlamp assembly and two impact sensors on either side of the front engine compartment. Is there any way to extract the codes with a typical OBD? I'd rather not wait for an appointment with the dealer.
#34
09-19-2012, 12:26 AM
Pro Wrench
Airbags disabled?
The only sure way I know of to disable the air bags is to disconnect the battery. That means you cannot start the vehicle etc. There are two fuses that provide power to the system, 5 amp F9P and 5 amp F68P both in the passenger side fuse box, but what they do, I do not know. I doubt removing them would set the air bags off however I also doubt that removing them would safe the system. Below is what is supposed to happen when a crash is detected; also there are more impact sensors than you might think.
IMPACT SENSORS
IMPACT SENSORS
Impact sensors are installed in the front and both sides of the vehicle. The use of multiple impact sensors provides shorter
air bag trigger times, through faster detection of lateral and longitudinal acceleration, and improves detection accuracy.
There are two front impact sensors attached to brackets on the body front support frame, just above each front longitudinal.
There are six side impact sensors located in the passenger compartment, as follows:
�� One attached to each front door.
�� One attached to the base of each B pillar.
�� One installed in each rear quarter, above the rear wheelarch.
Each impact sensor incorporates an accelerometer and a microcontroller powered by a feed from the RCM (restraints
control module) . The power feed also provides the interface connection through which the impact sensor communicates
with the RCM (restraints control module) using serial data messages. Acceleration is evaluated by the microcontroller and
transmitted to the RCM (restraints control module) , which then makes the decision on whether or not to activate the air bags and pretensioners.
When the ignition is switched on the RCM (restraints control module) supplies power to the impact sensors, which
perform a self test. After satisfactory self tests the impact sensors continually output 'sensor active' messages to the RCM (restraints control module) . If a fault is detected the relevant impact sensor sends a fault message, instead of the sensor active message, to the RCM (restraints control module) . The RCM (restraints control module) then stores a related fault code and illuminates the SRS (supplemental restraint system) warning indicator.
air bag trigger times, through faster detection of lateral and longitudinal acceleration, and improves detection accuracy.
There are two front impact sensors attached to brackets on the body front support frame, just above each front longitudinal.
There are six side impact sensors located in the passenger compartment, as follows:
�� One attached to each front door.
�� One attached to the base of each B pillar.
�� One installed in each rear quarter, above the rear wheelarch.
Each impact sensor incorporates an accelerometer and a microcontroller powered by a feed from the RCM (restraints
control module) . The power feed also provides the interface connection through which the impact sensor communicates
with the RCM (restraints control module) using serial data messages. Acceleration is evaluated by the microcontroller and
transmitted to the RCM (restraints control module) , which then makes the decision on whether or not to activate the air bags and pretensioners.
When the ignition is switched on the RCM (restraints control module) supplies power to the impact sensors, which
perform a self test. After satisfactory self tests the impact sensors continually output 'sensor active' messages to the RCM (restraints control module) . If a fault is detected the relevant impact sensor sends a fault message, instead of the sensor active message, to the RCM (restraints control module) . The RCM (restraints control module) then stores a related fault code and illuminates the SRS (supplemental restraint system) warning indicator.
Crash Signal
When the RCM (restraints control module) outputs any of the fire signals, it also outputs a hard wired crash signal to the
Engine Control Module (ECM) and changes the high speed CAN (controller area network) bus output message from 'no
crash' to 'crash condition'. The high speed CAN (controller area network) bus message is used by the CJB (central
junction box) and the FFBH (fuel fired booster heater).
On receipt of the crash signals:
When the RCM (restraints control module) outputs any of the fire signals, it also outputs a hard wired crash signal to the
Engine Control Module (ECM) and changes the high speed CAN (controller area network) bus output message from 'no
crash' to 'crash condition'. The high speed CAN (controller area network) bus message is used by the CJB (central
junction box) and the FFBH (fuel fired booster heater).
On receipt of the crash signals:
The ECM (engine control module) disables the fuel pump.
Operation of the FFBH is disabled.
The CJB (central junction box) enters the crash mode and: Activates all of the unlock signals of the vehicle locking system, even if the vehicle is already unlocked. After 3 seconds, the CJB (central junction box) activates the unlock signals again, in case a lock button is pressed during the crash, by flailing limbs for example. Ignores all locking and superlocking inputs until the crash mode is cancelled, when it returns the locking system to normal operation. Activates all of the courtesy lamps, except for the approach lamps. The activated courtesy lamps remain on until they are manually switched off at the lamp unit, or the CJB (central junction box) crash mode is cancelled, when they return to normal operation. Activates the hazard warning lamps. The hazard warning lamps remain on until cancelled by turning the ignition switch from position II to position I or 0, or until the crash mode is cancelled.
Activates all of the unlock signals of the vehicle locking system, even if the vehicle is already unlocked.
After 3 seconds, the CJB (central junction box) activates the unlock signals again, in case a lock button is pressed during the crash, by flailing limbs for example.
Ignores all locking and superlocking inputs until the crash mode is cancelled, when it returns the locking system to normal operation.
Activates all of the courtesy lamps, except for the approach lamps. The activated courtesy lamps remain on until they are manually switched off at the lamp unit, or the CJB (central junction box) crash mode is cancelled, when they return to normal operation.
Activates the hazard warning lamps. The hazard warning lamps remain on until cancelled by turning the ignition switch from position II to position I or 0, or until the crash mode is cancelled.
The crash mode is cancelled by cycling the ignition switch.
#35
09-19-2012, 06:05 PM
TReK
impact sensors do nothing. Do yourself a favor and check the fuse box, and behind it. its possible the crankshaft position sensor is acting or or the map sensor is doing something. You could be getting a really bad air leak all of sudden without the computer realizing it and shutting down. It can't throw a code because it stalls to quickly. If the flashers flash with the stall then you have an issue with the can system. possibly the can high. but if it turns over and then starts its not a can line. its possible the issue might be a loose fuel connection in the fuel tank itself. These have lots of parts inside the tank itself that could cause an issue.
#36
09-19-2012, 08:37 PM
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Thanks Rovin4life. Where might an air leak be coming from. Possibly a vacuum line? Or are you talking about the suspension. I'm going to go back to the cut in the road that causes the problem to manifest this weekend and I'm going to look for the flashers and door locks actuating. It's not close to home. Actually its only about 9 miles, but that's 45 minutes travel time in Chicago. Also, would a sudden sharp jarring cause the Crankshaft Position Sensor to shut the engine down? Is there any way to test it?
#37
09-20-2012, 11:01 PM
cfd01, Sorry I can't help either. Mine did it a couple times when offroading, but nothing since.
I might be heading out this weekend and I'll see if it does it again. But I checked over everything I coud visually and didn't see anything.
I did clean the TB and MAP sensor - but again, I don't know if it is really resolved yet.
Oh and when mine died, no flashers/doors unlocking. Just an immediate engine cut. Oh and no codes either.
I might be heading out this weekend and I'll see if it does it again. But I checked over everything I coud visually and didn't see anything.
I did clean the TB and MAP sensor - but again, I don't know if it is really resolved yet.
Oh and when mine died, no flashers/doors unlocking. Just an immediate engine cut. Oh and no codes either.
#38
09-21-2012, 03:07 PM
TReK
#39
09-29-2012, 03:04 PM
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I was able to reproduce the failure at the a fore mentioned spot. No flashers, no dorr unlocking. Took a couple cranks of the motor and everything was fine. Then it died turning the corner on the way home and my wife noticed that every time this happened I had less than a quarter tank of gas. Could I be having a problem with the fuel pump or sending unit as Rovin4life speculated?
#40
09-29-2012, 06:33 PM
Pro Wrench
More progress I would say.
My 88 Chev pickup would cut out on a hard left turn and less than a quarter tank; that meant so beating oncoming traffic with a fast left and low fuel level.
In this case, the problem seemed to be collapsed baffles within the fuel tank that allowed fuel to move away from the pickup point when the tank volume was low.
In your case, you must complement your wife, then try keeping the tank full and see if that helps. In other words, the problem may not be the bump thing or anything in the front but instead something fuel tank and fuel level related.
I guess the next experiment is to fill the tank and then hit the drop straight on and see if the engine dies; then later when the tank gets low, to try both hard and fast left and right turns. It sounds like you are on your way to finding a pattern to the problem. Once one can duplicate the problem, then the solution is not far away.
In this case, the problem seemed to be collapsed baffles within the fuel tank that allowed fuel to move away from the pickup point when the tank volume was low.
In your case, you must complement your wife, then try keeping the tank full and see if that helps. In other words, the problem may not be the bump thing or anything in the front but instead something fuel tank and fuel level related.
I guess the next experiment is to fill the tank and then hit the drop straight on and see if the engine dies; then later when the tank gets low, to try both hard and fast left and right turns. It sounds like you are on your way to finding a pattern to the problem. Once one can duplicate the problem, then the solution is not far away.