Unintended acceleration

[HOMEGAMEROOM]

(No, this isn't about unintended acceleration in the XLR (nor a debate about it and its causes), but I found this interesting tidbit from an online Car & Driver article. I haven't personally tried it; your mileage may vary.

Besides the obvious things to do with a car you can't stop (put it in neutral, downshift, HIT THE BRAKES), how would you turn off the engine of a car with an "On/Off" button like the XLR? You would just have to press and HOLD the button for a few seconds (up to 4 seconds could be needed) to turn the engine off. It won't shut the car off with a momentary push while rolling along since this could be done accidentally.

BTW, this certainly isn't the preferred method to stop a runaway car, since you lose all power steering assist and power brakes.

Drive safely!

 

[ccclarke]

Interesting question, since XLR doesn't have traditional-style brakes where the brake pedal is a physical part of the hydraulic system and the force applied acts as the accumulator to put pressure on the system. Intead, it uses brake pedal position sensors to determine how far and how fast the pedal is being applied. Lose power and it appears all you would have is left is the e-brake to slow the vehicle. Couldn't downshift since the TCM is a powered component. Maybe the Flintstones were on to something.

I've never understood why folks don't just shift into neutral an apply the brakes in stuck accelerator situations. --Hope I never have to find out though! (XLR has redundant accelerator sensors in case one fails.)

CC

 

[onalaska]

CC, Where did you read that? I'm looking at the factory service manual and it shows a brake pedal pushrod running from the brake pedal through the vacuum booster to the master cylinder.

 

[ccclarke]

Doh!!! I'm wrong. You're right -there is a pushrod going to the brake booster. The brake system does have a sensor to determine how far/fast the pedal travels though. Thanks for keeping me honest!

CC

 

[onalaska]

Doh!!! I'm wrong. You're right -there is a pushrod going to the brake booster. The brake system does have a sensor to determine how far/fast the pedal travels though. Thanks for keeping me honest!

CC

I glad we don't have brake by wire yet! Sure wouldn't want a Toyota with it!!

 

[ccclarke]

While we're on the subject. . .

<TABLE class=table-header-alt2 cellSpacing=0 cellPadding=3 width="100%" border=0><TBODY><TR><TD vAlign=top width="100%">Nature of Defect:
2. VEHICLE SPEED CONTROL:ACCELERATOR PEDAL </TD><TD class=stripe-three vAlign=top noWrap><TABLE cellSpacing=0 cellPadding=2 border=0><TBODY><TR vAlign=top><TD noWrap align=left width="50%">Recall Number:</TD><TD noWrap align=left width="50%">05V046000</TD></TR><TR vAlign=top><TD noWrap align=left width="50%">Dates Manufactured:</TD><TD noWrap align=left width="50%">Jul 2003 to Dec 2003</TD></TR><TR vAlign=top><TD noWrap align=left width="50%">Number of Vehicles Affected:</TD><TD noWrap align=left width="50%">19924</TD></TR><TR vAlign=top><TD noWrap align=left width="50%">Date Owners Notified On:</TD><TD noWrap align=left width="50%">N/A</TD></TR></TBODY></TABLE></TD></TR><TR><TD class=table-main colSpan=2>Vehicle: 2004 Cadillac XLR</TD></TR><TR><TD class=stripe-four colSpan=2>Defect Description:
CERTAIN PASSENGER VEHICLES FAIL TO COMPLY WITH THE REQUIREMENTS OF FEDERAL MOTOR VEHICLE SAFETY STANDARD NO. 124, 'ACCELERATOR CONTROL SYSTEMS.' IF ONE OF THE TWO ACCELERATOR PEDAL RETURN SPRINGS FAILS AND THE TEMPERATURE IS -22 DEGREES F TO -40 DEGREES F, THE ENGINE MAY NOT RETURN TO IDLE WITHIN THREE SECONDS, AS REQUIRED.
</TD></TR><TR class=table-main><TD colSpan=2>Consequence of Defect:
IF THIS WERE TO OCCUR, GREATER BRAKE PEDAL FORCE AND A LONGER DISTANCE MAY BE REQUIRED TO STOP THE VEHICLE.
</TD></TR><TR class=stripe-four><TD colSpan=2>Corrective Action:
DEALERS WILL REPLACE THE ACCELERATOR PEDAL ASSEMBLY. THIS RECALL BEGAN ON MARCH 8, 2005. OWNERS MAY CONTACT CADILLAC AT 1-866-982-2339 OR PONTIAC AT 1-800-620-7668.
</TD></TR></TBODY></TABLE>


But honestly officer . . . there's a recall for this, and I was on my way to the dealership . . .

CC

 

[HOMEGAMEROOM]

I'm printing this out and keeping it with me at all times!!!!

That's pretty interesting!

 

[XLR KEN]

While we're on the subject. . .

<TABLE class=table-header-alt2 cellSpacing=0 cellPadding=3 width="100%" border=0><TBODY><TR><TD vAlign=top width="100%">Nature of Defect:
2. VEHICLE SPEED CONTROL:ACCELERATOR PEDAL
</TD><TD class=stripe-three vAlign=top noWrap><TABLE cellSpacing=0 cellPadding=2 border=0><TBODY><TR vAlign=top><TD noWrap align=left width="50%">Recall Number:</TD><TD noWrap align=left width="50%">05V046000</TD></TR><TR vAlign=top><TD noWrap align=left width="50%">Dates Manufactured:</TD><TD noWrap align=left width="50%">Jul 2003 to Dec 2003</TD></TR><TR vAlign=top><TD noWrap align=left width="50%">Number of Vehicles Affected:</TD><TD noWrap align=left width="50%">19924</TD></TR><TR vAlign=top><TD noWrap align=left width="50%">Date Owners Notified On:</TD><TD noWrap align=left width="50%">N/A</TD></TR></TBODY></TABLE></TD></TR><TR><TD class=table-main colSpan=2>Vehicle: 2004 Cadillac XLR</TD></TR><TR><TD class=stripe-four colSpan=2>Defect Description:
CERTAIN PASSENGER VEHICLES FAIL TO COMPLY WITH THE REQUIREMENTS OF FEDERAL MOTOR VEHICLE SAFETY STANDARD NO. 124, 'ACCELERATOR CONTROL SYSTEMS.' IF ONE OF THE TWO ACCELERATOR PEDAL RETURN SPRINGS FAILS AND THE TEMPERATURE IS -22 DEGREES F TO -40 DEGREES F, THE ENGINE MAY NOT RETURN TO IDLE WITHIN THREE SECONDS, AS REQUIRED.

</TD></TR><TR class=table-main><TD colSpan=2>Consequence of Defect:
IF THIS WERE TO OCCUR, GREATER BRAKE PEDAL FORCE AND A LONGER DISTANCE MAY BE REQUIRED TO STOP THE VEHICLE.

</TD></TR><TR class=stripe-four><TD colSpan=2>Corrective Action:
DEALERS WILL REPLACE THE ACCELERATOR PEDAL ASSEMBLY. THIS RECALL BEGAN ON MARCH 8, 2005. OWNERS MAY CONTACT CADILLAC AT 1-866-982-2339 OR PONTIAC AT 1-800-620-7668.

</TD></TR></TBODY></TABLE>


But honestly officer . . . there's a recall for this, and I was on my way to the dealership . . .

CC

HOMEGAMEROOM,

If you expect to use this as an excuse, be sure to NOT point out that the temp must be between "-22 and -40 degrees F." I don't think the excuse will work this summer with the top down............

XLR KEN