'95 Wagon, won't start in "N", /ASR
 

Hi,
My 1995 E320 124 wagon has developed the ASR light on recent cold morning starts, when I hit the brakes; light comes on and car goes LIMP. I tried to restart while coasting in Neutral. No go. STarter was not energized, did not turn over.
Should the car start in Neutral?
Have not pulled the codes yet.

neutral safety switch? check that?

Yes, it should start in neutral.

If you're lucky, it's only an OVP [over protection relay] behind battery.

But you should use Arthur Dalton's code tester before you start throwing parts at it.

How many miles?

Was engine wiring harness or throttle body [actuator] ever replaced?

Any other mechanical or electrical problems?

WHat is an OV relay? I have 145 k miles on what otherwise feels like a new car. I have only had it for a year, and do not know about head gasket , wiring harness, throttle body, but suspect they were not done yet. I saved the code reader post, and will build one soon. Thanks

Hi Paul,

When you start doing searches on "ASR" and "limp mode", you'll might be a little overwhelmed. First thing tomorrow is to go to Radio Shack and buy parts to make Arthur's Code Reader. You'll need at least 9" for each wire color. 10 or 12 ga. is good. I mounted the switch and light in a 35 mm film container, but any pill container about 1 x 2" or larger will work. The black box [2w x 3L x 1d"] you plug into is in front of battery towards engine.

Read the codes a few times to make sure you're doing it correctly and post your results here.

Easy things to check first:
Vacuum tubes / hoses.
# The hard plastic ones can be replaced with standard rubber vac hoses. OEM was color coded, yours may differ i replaced. But keep some of the hard plastic to make connectors for rubber hoses into elbows.
1] Behind brake master cylinder booster: feeds engine & tranny !!!
2] Under black plastic front engine cover
3] Air pump and others you can worry about later [Door locks & Climate Control]

Your questions:

OVP aka Over Protection Relay has blue fuse on top. Name implies what it does. Easy diy.

Head Gasket: Usually leaks at corner closest to passenger. Open oil fill cap, if just oil you're not mixing oil & water. If grayish or yellowish moose, you're mixing = ng.

Wiring harness is problematic the more you move it. Hopefully, with 145k it was replaced. Easy place to check is wiring at thermostat housing. An electrical connector has a black sheathing over two wires. Either slide back or carefully cut the sheathing to reveal the wires. If the insulation is dry or brittle it's ng. If smooth and pliably it's ok. OEM harness was made with a "green friendly" insulation that unfortunately couldn't withstand heat. [MB still doesn't admit they screwed up].

Throttle Body aka Actuator [see pik in my profile photos] located between 3rd & 4th intake tubes, fed by air intake tube. $450 to rebuild mine, easy diy. Uses same ng wire insulation as engine harness.

Oracle is correct about checking neutral safety switch. It's located on bottom side of tranny. A PIA, but still a diyer.

Use 'fastlane" on this site to get idea of parts piks & cost.

Thanks. Off to Radio Shack....

le sigh,,,,

CODES ; (I even had a film canister).
Pin #8 flashed 8 times.
Pin #14 flashed 14 times.

I'm not 100% sure on this, but the no start in neutral condition you described might be normal. These cars have a safety feature built into the start system to prevent crash engagement of the starter. Once the starter has been engaged once, the key must be returned to the initial (position 0) before the starter will engage again............................

Goo d thought... I am pretty sure I cycled the key to OFF, then tried to start. All the lights lit up, but no action at the starter.

CODES
Pin #8 flashed 8 times. => Idle Speed Control [ISC]
Pin #14 flashed 14 times. => Closed Throttle Position Contact Switch

A number of different dysfunctional items can cause these codes. I'm not the "best" diagnostician, so it's better to have someone else on this list and / or an inde shop help you with specifics. You used an appropriate title for this thread, so much more knowledgeable people than me will contribute and help you.

I assume your wagon has ASR, but you should check and post that info.

How does the engine wiring harness insulation look? This is important to know...

What's the condition [OEM vs replaced] of ALL the vacuum hoses & tubes?

What other performance [engine, transmission & electrical] items have been repaired or replaced?

This '95 wagon does have ASR, and the 'tire chain' button.
Head gasket is solid.
I can see that the PO put in a torque converter, and some trans work.
Have not cut open the wiring harness. The car was dealer maintained previously, and I am hoping the harness was done.
The car runs as new; But, just recently, on the cold mornings, in the first few minutes after start, when I hit the brakes, is goes ASR light ON, and LIMP mode., Car restarts and is fine. I should look into why I cannot do a rolling start in neutral.

Taillight assembly, the piece where the bulbs snap into, can develop contact issues. Funny that it happens when you hit the brake. Brakelight is activated then. I replaced my left one and fixed the ASR issue

Will, I like that. It only happens just as I hit the brakes. thanks

You might also have an issue with the stop light switch on the brake pedal. Also, when you apply the brakes, the subsequent lowering of RPM might also be triggering Limp Mode, and would not necessarily be related to the brake switch/lights.

You specifically stated the problem occurs only on cold mornings. My car does the same and the cause was traced to a faulty coolant temperature sensor. Once the engine/coolant warms (and, presumably, when the sensor is replaced) the problem goes away.

Does your cruise control work? If not, that might be confirmation of a bad stop lamp switch at the brake pedal. If the switch is good, you may have a defective throttle actuator. (both codes you referenced can be associated with a defective throttle actuator)

Like Bob, I'm not the best diagnostician but maybe the above thoughts will give you a few more ideas to follow up on........

Coolant temp sensor, Yikes! How weird.
I picked up a brake light switch today for $12, since this ALWAYS happens to this car just when I hit the brakes, 2 miles or so after a cold morning start. Won't be able to get the stop light switch in before Thursday, and will report back.
Thank you to all for your input.

WOuldn't it be nice if it is that simple?

Yes, Cruise works perfectly.....

Pull up a starting wiring diagram and figure out what should be getting 12volts, what is a load. Make sure you check these things:

1. Good battery
2. good connections that arent dropping volts where no volts should be dropped.
3. Starter solenoid
4. Igntion switch
5. neutral safety switch
6. corrison on any connections
7. check for opens, shorts

Thanks for the input. I will install the brake stop-light switch by the weekend, check the contacts in the bulb housing, and certainly try to find the Neutral Safety switch and look at the contacts. I guess that will be the next item to replace.

For Neutral Safety Switch instal info go here:
http://www.peachparts.com/shopforum/showthread.php?t=84519&highlight=Neutral+Safety+Switch

I don't have link, but here's additional info from post by Arthur Dalton...
The switch is tight, but straight foward to replace.
It is mounted to the trans with 2 10mm bolts. The bolt holes are oblonged for rotational adjustment.
The only tricky part for first timers is the plug has a white locking ring on it that requires you to turn the ring to the unlock position in order to unplug the harness..and there is also a pin in the sw. acyating lever that has to line up with the hole on the shift arm to lock that into proper location upon reassembly..but that is pretty much evident once you are down there.
Adjustment is correct when you have a starter engagement in both N and P and back-up lamps in R.
You may also want to take a look at the shifter rod rubber bushing for wear while you are there ..they are usually worn and simple/cheap to replace.

###

thanks for that link!

Update
 

I replaced the brake stop-light switch, but have not had a cold enough morning to know if that helped. I also realized that the neutral Safety Switch is out of adjustment ( I can start in neutral if I push the shifter forward a bit). I will adjust the switch on Friday, and be able to do a rolling start if I see LIMP mode again. Will advise.

UPDATE:
The short story; ASR light and LIMP mode, ONLY occur when the outside temp is below 20 degrees F, and only in the first 5 minutes of driving, usually occurring when I come off the throttle, or hit the brakes. If I first let the car warm-up for 10 minutes, I can drive off with no problem.

I have cleared codes and pulled the same codes repeatedly; 8 blinks on pin #8 (idle speed control system at upper or lower control stop or LIMP indicated), and 14 blinks at pin #14 (closed throttle position contact switch).

I have Replaced the brake light switch;
Checked wiring harness (looks solid under the black cover at the engine front);
Replaced the wrong coolant temp sensor (replaced single contact sender instead of the 3 wire sender which feeds the computers);
Checked that I do have the newer part # for the OVP relay;
Looked all tail/brake lamps;
The Neutral Safety Switch does need adjustment, not done yet...

Co-incidentally, the car is in the shop today, as the Air Pump commenced to making a terrible racket, and must be replaced.

Thanks for any further thoughts.

You wrote
"The short story; ASR light and LIMP mode, ONLY occur when the outside temp is below 20 degrees F, and only in the first 5 minutes of driving, usually occurring when I come off the throttle, or hit the brakes. If I first let the car warm-up for 10 minutes, I can drive off with no problem."

Does make one think of temperature sensor / sender. Ah, but there's more than one.

Sorry to hear about the Air Pump, but better to have it checked before its clutch freezes and wipes out serpentine belt.

Here are two links regarding Air Pump Clutch that may save you some money.

w124 Smog Air Pump rebuild - ShopForum
http://www.peachparts.com/shopforum/showthread.php?t=186139&highlight=air+pump+clutch

94 E320 Air Pump Issues....What to do? - ShopForum
http://www.peachparts.com/shopforum/showthread.php?t=177803&highlight=air+pump+clutch

Doing a search on Air Pump Clutch will provide enough reading for today. Take note of post dates regarding parts prices.

I wonder if you could have a bad wire harness on the throttle actuator. Perhaps when everything is cold and stiff, you have some internal shorting, then, after some warm up the wire harness loosens up and no longer shorts. If I remember correctly the codes you are getting point to a throttle actuator problem. Kind of a long shot but you never know.

J. M. van Swaay