83 300td turn key nothing happens - PeachParts Mercedes-Benz Forum

big-a · #1 07-05-2009, 02:05 PM

ok, sorry my first post is going to be a long one, but i'd appreciate any help i can get. i have an intermittent problem that is becoming worse. it started on a road trip. i stopped at a gas station after a couple hours on the highway; when i tried to start the car to leave, i turned the key; all the appropriate dash lights came on; the glow plug lights came on, but the car did not turn over--like the battery was dead or something. i got a jump and it fired right up. i took it to advanced auto; they tesed the battery and alternator--there was nothing wrong with them. i turned it off and on several times with no problems so i went on. when i got to my destination a few hours later, and turned it off, i tried to turn it back on, and nothing again. i let it set a few hours, and it fired right back up. and i had no problems driving around town while i was there. on the way to my next location (7 hours away) i stoped at a gas station and...nothing. i let it sit for a while and it fired up. so it seemed to me that this problem only happened after long stretches on the highway. however, now that i am home the problem is happening around town, and even first thing in the morning, after sitting all night.
my car is an automatic transmission

and i recently changed the shifter bushings (the day before i left--but i made from columbus, oh to washington dc, then to philadelphia, then to nyc (all over the course of about 5 days) with no problems (i did change a headlight in nyc--just thought i'd throw that out there

)
when the problem is happening, it does not start in any gear, including neutral
connections the battery are tight
connections to the started are tight
ground to the body is tight
don't know what else to say.
thanks for any help!

79Mercy · #2 07-05-2009, 02:10 PM

Remove and clean both battery terminals.

I had a similar problem with a different car.

kerry · #3 07-05-2009, 02:26 PM

This is a very common problem with lots of threads on it. Search on it to find the possible problems and various solutions. There is a 90% chance that jumping terminals 1 and 3 in the plastic junction box on top of the right front fender in front of the battery will start it every time.

Road trip rule #1: If your starter fails on a roadtrip and you don't know why, don't shut off your engine until you get home.

Diesel911 · #4 07-05-2009, 02:31 PM

As previously stated if you have a Terminal Block to the right of the Battery you can use a jumper wire or a Remoter Starter Button connected from the either of the screws (they are actually connected together) to the left; to the small screw on the right.

I am thinking it could be the Neutral Safety Switch going bad (the switch on the Transmission that only allows you to start in Park or Neutral).

Part of what you say happens when I have forgotten to put the Gear Shift in Park. Everthing; all the electrical stuff seemed to work but when I tried to start nothing. After putting it in Park the car started (Neutral Safety Switch doing working properly).

Why it would not work and work later I cannot say.
It could also be your Ignition Switch itself is going bad.

If the Netureal Safety Switch in the thumbnail below was near where you were doing the Shift Bushing repair it could be related to your problem.

FineOlBenz · #5 07-05-2009, 04:12 PM

It has been known for the ignition switch to go bad. It will make poor contact in the start position. Try the jumper wire on the right front fender as previously mentioned. CAUTION; Make sure it's not in drive or reverse! It will start and take off without ya!

big-a · #6 07-05-2009, 04:33 PM

Quote:

Originally Posted by Diesel911

As previously stated if you have a Terminal Block to the right of the Battery you can use a jumper wire or a Remoter Starter Button connected from the either of the screws (they are actually connected together) to the left; to the small screw on the right.

I am thinking it could be the Neutral Safety Switch going bad (the switch on the Transmission that only allows you to start in Park or Neutral).

is this something that i attach and leave on, (temporaily of course, until i figure out and fix the problem) or is it a quick fix where i just touch the two screws together with the wire and then take off when it starts? i'm assuming the ignition has to be in the run position (forget which number that is--2 maybe?)

if this works, is it any indicator of any specific problem?
does it rule out any specific problems?
Thanks for everyone's help btw.

Biodiesel300TD · #7 07-05-2009, 05:26 PM

It sounds like the neutral safety switch. Next time it happens try shifting through the gears a couple of times and see if the starts. Also the transmission has to be in neutral or park for the car to start. So make sure it is in one of those. I've made that mistake more than once myself.

snookwhaler · #8 07-05-2009, 05:51 PM

This happened to me. Turned out to be bad shifter bushings.

Running it back through the gears a couple times would allow it to start for a while. Then it finally quit. Replaced the bushings, problem solved.

GWNorris3rd · #9 07-05-2009, 06:38 PM

I guess my car has a direct line to this forum, as I just went out to start it and everything lit-up but would not engage the starter... turned it off, ran the shift lever though all gears put it back into Park and turned on the key, glowed the plugs and it started right up! Looks like my neutral switch and bushing are going... thanks, looks like next week's project.

Diesel911 · #10 07-05-2009, 11:08 PM

Quote:

Originally Posted by big-a

is this something that i attach and leave on, (temporaily of course, until i figure out and fix the problem) or is it a quick fix where i just touch the two screws together with the wire and then take off when it starts? i'm assuming the ignition has to be in the run position (forget which number that is--2 maybe?)

if this works, is it any indicator of any specific problem?
does it rule out any specific problems?
Thanks for everyone's help btw.

If using the Terminal Block the Crank the Starter works it will only mean there is no problem from the Terminal Block down to the Starter; and of course will allow you to drive start and Drive your car.
You will still have to find out why the starting Circuit is not getting electricity. My bet is on that Netural Safety Switch with a 2nd choice of the Ignition Switch (it is at the bottom of the Steering Wheel Lock).
If you can locate the Netural Safety Switch wires you can test them with a meter for Voltage. In the DIY section they may have a Wiring Diagram.
It would not hurt to take a good look at the fuses also; and also the ends of the fuses to make sure they are not coroded.

The Jumper Wire is just a piece of wire with the 2 ends bare that you apply to the terminal block to Crank the Starter. After the Engine starts just remove the jumper wire and let the Engine rune.

The Remote Starter Button is a switch with small clips on the end like jumper cables that you would clip onto the Terminal Block; afterwhich you press the hand held button to Crank the Starter. Again after the Engine is running you remove the Remote Starter Button.
You will need to have someone do the Glow Plug Cycle for you or be very fast.
Below is a pic of 1 type of Remote Starter Button.

[A Push Button Switch (You could buy an inexpensive Remote Starter Button and splice on longer wires with eyes on the end) could be run into the inside of the car and the wires attached with eyes to the Terminal block if you have an urgent need to keep your Car running and you do not want to open the Hood to Jump the Terminal Block to start the car.]

big-a · #11 07-06-2009, 12:06 AM

thanks a bunch. i gave it a try and quickly learned that i would not leave it on! i kinda like the button idea just for fun though--, although it struck me that these cars are pretty easy to steal except for the locked steering, but if you are one of the many who has removed or blocked the steering lock, one could be home free. NOT THAT I AM ENDORSING THAT IN ANY WAY, just kind of a scary thought to me. but anyway...
i think i'm going to try the neutral safety switch, it makes the most sense and seems pretty easy. i'll let you know how it turns out.

kerry · #12 07-06-2009, 09:14 AM

You should be able to jump the wires on the NSS to test it. Given the fact that you were changing the shifter bushing, I think there is probably an issue with the NSS. However, it is also very common to have poor connections somewhere in the ignition circuit which is why some people have installed a relay to get more power to the starter.