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ASR Light

On Friday afternoon, my family and I drove north from Houston to the Dallas-Fort Worth Metroplex for the weekend. Specifically, the purpose was to attend the GTG that texas993 was hosting at his home, and also to visit samiam44 at his home in the DFW area. Had a great time all weekend, but that's a story for another post.

We were traveling north on I-45, about 50 miles south of Dallas, about 80 MPH (in a Texas 75 MPH speed limit zone), and all of the sudden my E500 shuddered and dropped down into limp-home mode, and the ASR light (but not ABS) light went on, on the dashboard. I continued to drive at that speed for about another 10 miles, though it took considerably more pressure to keep the gas pedal pressed to maintain that speed.

Eventually, we got off at a suitable exit, and I pulled over and shut off the car for a few seconds. Turned it back on and the ASR light disappeared, and had no problem the rest of the way. We continued to drive the car all around the DFW area all day on Saturday and Sunday and had no problems. This afternoon we left about 2:30 PM and arrived home around 6:15 PM. Speeds were fairly high during the trip home, ranging from 75-100 MPH over long distances. No ASR light or any other anomalies.

This was the first time in nearly 10.5 years of ownership that the car had dropped into LHM. I checked and cleared codes at texas993's house and will continue to monitor the car. My wife is driving it daily as I'm working on her wagon, so hopefully something else pops up ... or it's just a one-time anomaly.

Couple of notes on the running of the car, though. The temps in Dallas were fairly cold, being in the 37-43F range today for the duration of the trip home. I absolutely could not get the car to go above 85C in coolant temp the entire way home, even driving at 95-100 MPH for 10-20 miles at a time (sustained load). The needle literally never got off the "80" number the entire day.

This is in contrast to when ambient temps are 75F and higher, when the needle ranges 90-105C. It's why when I lived in Portland I never noticed high temps (except on extremely hot summer days, which are fairly few and far between in Portland) -- most days average in the 40s through 60s year round in Portland. It's really amazing how sensitive the .036 is to ambient temps.

Cheers,
Gerry


P.S. This morning I walked the quarter-mile from our hotel in downtown Dallas to Dealey Plaza, in about 34F temperature. Brrr! This was the site where John F. Kennedy was assassinated in November, 1963. You can see the "X" on the pavement in the roadway (left of center in the first photo below) where the actual deadly shot occurred. In the second photo, you get a good overview of the "grassy knoll" where Abraham Zapruder [accidentally and sadly] shot his famous film of the assassination when it occurred. You can also see a small memorial plaque next to the road, in the grass, opposite the marked spot.

2013-12-22 08.16.35.jpg 2013-12-22 08.16.22.jpg

I took these photos from under the trees in the very center of this photo:
91.jpg
 
This was the first time in nearly 10.5 years of ownership that the car had dropped into LHM. I checked and cleared codes at texas993's house and will continue to monitor the car. My wife is driving it daily as I'm working on her wagon

There you have it: It's her fault.

Not to get too far off subject, I never gave much thought to the conspiracy theories surrounding this shooting because it happened slightly before I was born. But one thing I found troubling is that the government never released the autopsy report to the general public. What do they have to hide?
 
Gerry, maybe you should post your ASR issue on Benzworld? There seems to be quite few experts over there.

:trolls:
 
Gerry, maybe you should post your ASR issue on Benzworld? There seems to be quite few experts over there.

:trolls:
I'm banned there so I can't post using my account.

With regard to the conspiracy theories ... the Secret Service and Bobby Kennedy immediately (and illegally) took custody/control of JFK's body, and it was buried quite quickly after his death, so yes, a proper autopsy was never performed.

All I know was that looking up to that Texas School Book Depository 6th floor window, to the roadway where JFK was shot ... a moving vehicle ... it was a couple hundred yards at least. If it did come from that building, the shooter was a crack shot.
 
I'll contact you on this Gerry. I have a few idea's

Sent from my SPH-M930BST using Tapatalk 2
 
SUCCESS!

After driving 500 mi., I consider the ASR problem solved.

Lesson learned:

BEFORE you do what I did, (cut out an ASR pump and accumulator from a used car), try changing your brake fluid.

There must have been an air pocket caught in the system for the last year causing the pump to vibrate and ASR light to illuminate.

After brake fluid change, pump stopped vibrating and ASR light remains extinguished!
 
Hi Gerry,

My car's a'92 with 190k on it. I've had the ASR light come on and been put in to LHM a number of times in the past 6 months.

Restarting the car has fixed it each time to date but I'd really like to resolve the issue.

Have you gotten any more insight into the issue?

Thanks,

Steve
 
Hi Gerry,

My car's a'92 with 190k on it. I've had the ASR light come on and been put in to LHM a number of times in the past 6 months.

Restarting the car has fixed it each time to date but I'd really like to resolve the issue.

Have you gotten any more insight into the issue?

Thanks,

Steve
Nope, the car has behaved perfectly since that time.
 
Thanks - seems to be part of the charm I take it :-)

I'll let post something if and when I get to the bottom of it..
 
I think it has been nearly a year since my last limp home mode episode.
Car has been running great since.
I did what you guys have done. ie. . . stop car, restart car. That seemed to work, however I would have to explore this issue further IF it happened more often.
 
Thanks - seems to be part of the charm I take it :-)

I'll let post something if and when I get to the bottom of it..
Pull codes. Could be the NSS. Check the date code on your ETA, if it's original, that's another likely culprit. I believe the NSS and ETA are the primary causes of the limp mode.

:5150:
 
After letting my car sit for nearly three weeks, I started the car and heard the ASR pump run.
I knew what was coming next. . . ASR light illuminated.

I am prepared this time.
1. I bled the SP screw on the ASR pump with the engine OFF.
2. Hooked up my pressure bleeder to the brake fluid resivior.
3. Started engine with the SP valve open and bled till no brake fluid bubbles (very little fluid).
4. Closed SP valve.
5. Let ASR pump run for about 30 seconds.
6. Shut down engine and disconnected pressure bleeder.

Problem solved. No ASR light.
Hypothesis: Letting the car sit that long developed an air bubble in the ASR pump. Don't know why.
 
After letting my car sit for nearly three weeks, I started the car and heard the ASR pump run.
I knew what was coming next. . . ASR light illuminated.

I am prepared this time.
1. I bled the SP screw on the ASR pump with the engine OFF.
2. Hooked up my pressure bleeder to the brake fluid resivior.
3. Started engine with the SP valve open and bled till no brake fluid bubbles (very little fluid).
4. Closed SP valve.
5. Let ASR pump run for about 30 seconds.
6. Shut down engine and disconnected pressure bleeder.

Problem solved. No ASR light.
Hypothesis: Letting the car sit that long developed an air bubble in the ASR pump. Don't know why.

Arguing with "fixed" is usually a bad idea, but FYI, bubble formation isn't very likely. If that's a pattern you've seen more than once, it is possible that your ASR pre-charge pump (the one under the master cylinder) is inoperative. They can form a corrosion deposit and/or get debris in the pump gears that seizes them up. This is a more frequent occurrence on garage queens, and/or cars that are driven so gently that the ASR pressure reservoir doesn't get depleted enough to require a "recharge". It is usually discovered as a lurking time bomb on the technician that actually attempts a proper brake fluid change on an older car, which of course includes draining and refilling the pressure reservoir fluid circuit. You can usually fix the pumps with some careful disassembly and gentle cleaning. If that condition happens again, holler back here.


Also note this. If your battery is a little flat, the low voltage condition just as, and upon starting can leave traction controls inoperative. The control units will usually, but not always store voltage related fault codes in those cases. operation is usually restored by a key cycle. I don't think that's what is happening with you because you stated that you heard the pump running, and during those low voltage events, they usually remain off until the key is cycled.

:klink:
 
I pulled an ASR pump and accumulator off of a 93 400E last year, just to have in reserve, so time will tell if I need them.
 
The moral to this entire thread can be summed up by saying,

When bleeding brakes, do the entire procedure, ie. . . bleed the SP valve on the ASR pump at the end.

My indy mechanics omitted this last step a couple of years ago when I changed brake fluid, thereby illuminating the ASR light.

Now that I have the brake bleeder, understand the system a little better, and have some experience, I think I may have come to the conclusion of this thread. Only time will tell.
 
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I have had an ASR light up, not limp home mode style.
I had a broken plastic piece on the throttle cable so I was tinkering with it and trying to get a little slack out of it.
Inadvertently, I did not have everything adjust properly. Even while it was broken, I backed of the plastic screw, still tinkering.
The ASR stopped coming on. Moral of the story, I think having mal-adjusted linkages or throttle cable can cause an ASR light to come on.
I believe....
 

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