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I bought a w210 e55 and was told all it needed was a transmission service and it will be good because the transmission was leaking. After doing it the car drove but was in limp mode. I cleared codes and transmission slipping code went away but front right speed sensor codes remained, after replacing sensor nothing changes, found cut wires from sensor and repaired them and still had codes. there is one other wiring harness that is completely chewed through but I cant find where it goes, also a green plastic straw thing broken coming from the firewall of the car. Also missing what I think is the egr plug that goes to the yellow plug. The limp mode makes it stuck in what I think is 2nd or 3rd gear and thuds into gear when putting it in drive or reverse. Does anyone know where the wires go and what they are for. What could cause this and if there is a fix like coding that fault out of finding where those wires go. Other small things are that the ac doesn't work and the 2 fans on the front don't spin. The dash shows bas esp abs faults. The codes aren't po7 so I don't think its the conductor plate.
I bought a w210 e55 and was told all it needed was a transmission service and it will be good because the transmission was leaking. After doing it the car drove but was in limp mode. I cleared codes and transmission slipping code went away but front right speed sensor codes remained, after replacing sensor nothing changes, found cut wires from sensor and repaired them and still had codes. there is one other wiring harness that is completely chewed through but I cant find where it goes, also a green plastic straw thing broken coming from the firewall of the car. Also missing what I think is the egr plug that goes to the yellow plug. The limp mode makes it stuck in what I think is 2nd or 3rd gear and thuds into gear when putting it in drive or reverse. Does anyone know where the wires go and what they are for. What could cause this and if there is a fix like coding that fault out of finding where those wires go. Other small things are that the ac doesn't work and the 2 fans on the front don't spin. The dash shows bas esp abs faults. The codes aren't po7 so I don't think its the conductor plate.
Without photos I have no idea what you are talking about.
Transmission: mechanical/hydraulic faults will put the car into limp mode but will clear temporarily when you turn the key off and then back on. Electrical faults the transmission goes into limp mode and stays there until the faults are cleared using diagnostic system. Current faults bad; stored faults not so bad but alert you to an issue that may reoccur again in the future.
Accelerator pedal OR speed sensor? Which one is it? With a decent diagnostic system you can monitor the voltages from the accelerator pedal and you can monitor the speed sensor. That allows you to focus on the real issue rather than flipping a coin or pulling out the parts shotgun.
The last fault tells you you have a bad connection somewhere in the circuit for the speed sensor. If it is the speed sensor for which you repaired the wires, did you solder or use butt connectors? Did you verify there are no corroded connectors inline? Did you see if the speed sensor with new harness is available from the dealer? The fact the code is current tells you there is a faulty connection in the circuit or the sensor has failed.
FWIW, on my W210 I use an old version of STAR/Xentry and a Foxwell multi-system scanner with 38-pin connector. The Foxwell is a quick diagnostic and corrects most problems; the STAR/Xenty goes so far as to allow monitoring of real-time values plus "bit-banging" in the modules (use carefully as one can 'brick' their car).
You don't say what year your W210 E55 is but try the attached schematics; they are for a facelift W210 but are virtually identical to the 1999 pre-facelift. (eg, fuse number shifted one digit during the facelift).
EDIT: from the photos...voltage is faulty, resistance too low. Sounds like a potential short circuit to chassis or a corroded connector causing a voltage drop because of increased contact resistance.
Last edited by bbirdwell; Oct 17, 2024 at 04:40 PM.
Without photos I have no idea what you are talking about.
Transmission: mechanical/hydraulic faults will put the car into limp mode but will clear temporarily when you turn the key off and then back on. Electrical faults the transmission goes into limp mode and stays there until the faults are cleared using diagnostic system. Current faults bad; stored faults not so bad but alert you to an issue that may reoccur again in the future.
Accelerator pedal OR speed sensor? Which one is it? With a decent diagnostic system you can monitor the voltages from the accelerator pedal and you can monitor the speed sensor. That allows you to focus on the real issue rather than flipping a coin or pulling out the parts shotgun.
The last fault tells you you have a bad connection somewhere in the circuit for the speed sensor. If it is the speed sensor for which you repaired the wires, did you solder or use butt connectors? Did you verify there are no corroded connectors inline? Did you see if the speed sensor with new harness is available from the dealer? The fact the code is current tells you there is a faulty connection in the circuit or the sensor has failed.
FWIW, on my W210 I use an old version of STAR/Xentry and a Foxwell multi-system scanner with 38-pin connector. The Foxwell is a quick diagnostic and corrects most problems; the STAR/Xenty goes so far as to allow monitoring of real-time values plus "bit-banging" in the modules (use carefully as one can 'brick' their car).
You don't say what year your W210 E55 is but try the attached schematics; they are for a facelift W210 but are virtually identical to the 1999 pre-facelift. (eg, fuse number shifted one digit during the facelift).
EDIT: from the photos...voltage is faulty, resistance too low. Sounds like a potential short circuit to chassis or a corroded connector causing a voltage drop because of increased contact resistance.
I thought I attached the video but I guess I didn't. https://photos.app.*******/qQVs4CDi6QMiRz9m8. The video shows the wiring harness I think I need but don't know what it is or called.
You can clear codes and you can also code out modules depending upon options.
To help you figure out what is what, go to the parts catalog. You're going to want the W210, 210.074, 66G (because yours is a 2000 or later model year). Go to section 54, subsection 121, Electrical equipment and instruments. This will give you an idea of what plugs are located on the engine harness. I rather doubt the harness is still available but it wouldn't hurt to inquire at the dealer; I picked up a door harness years ago that had been sitting on a shelf in Germany for over 16 years.
You really need the schematics in WIS (Workshop Information System). Attached are some tips for using those schematics. Brown wires are either grounds or CANBUS Lo wires.
This won't be easy but it is doable. Wiring damage caused by rodents is always a PITA.
The plastic tube sources from the back of the intake manifold, then routes into the passenger side fender well, then back out of the fender well into the interior HVAC system. It is the vacuum source for the flapper valves under the dash.
The missing connector on the EGR valve appears to be a sensor according the parts list; the connector wires route into the fuel injector harness fastened to the fuel rail on the passenger side.
When repairing the wires, I recommend inserting a new piece of wire long enough (6-8"?) to easily manipulate and make a service loop to take up the extra length; makes it much easier to repair the harness if you go that route. Heat shrink tubing over the wire, twist wires for a good mechanical connection, solder and then shrink the tubing over the solder joint. EDIT: looking at the video, it appears you used a crimp butt connector to repair at least one wire. That is guaranteed to be a failure point now or later. Do it correctly the first time or you will be doing it again later and usually at the most inopportune time.
HVAC issues can be identified by reading the codes directly off of the AC control panel; an internet search will find multiple threads explaining how to do so.
WIS schematics would help you to identify what those three wires should be attached to.
Front fans, only one is driven by an electric motor that is controlled by a fan control module (located under the passenger side front fender attached to the frame). The second fan is driven by the first fan via a small v-belt.
I hope you got this car really cheap. And as the expression says, "Nothing is more expensive than a cheap Mercedes".
Last edited by bbirdwell; Oct 24, 2024 at 11:47 AM.
The plastic tube sources from the back of the intake manifold, then routes into the passenger side fender well, then back out of the fender well into the interior HVAC system. It is the vacuum source for the flapper valves under the dash.
The missing connector on the EGR valve appears to be a sensor according the parts list; the connector wires route into the fuel injector harness fastened to the fuel rail on the passenger side.
When repairing the wires, I recommend inserting a new piece of wire long enough (6-8"?) to easily manipulate and make a service loop to take up the extra length; makes it much easier to repair the harness if you go that route. Heat shrink tubing over the wire, twist wires for a good mechanical connection, solder and then shrink the tubing over the solder joint. EDIT: looking at the video, it appears you used a crimp butt connector to repair at least one wire. That is guaranteed to be a failure point now or later. Do it correctly the first time or you will be doing it again later and usually at the most inopportune time.
HVAC issues can be identified by reading the codes directly off of the AC control panel; an internet search will find multiple threads explaining how to do so.
WIS schematics would help you to identify what those three wires should be attached to.
Front fans, only one is driven by an electric motor that is controlled by a fan control module (located under the passenger side front fender attached to the frame). The second fan is driven by the first fan via a small v-belt.
I hope you got this car really cheap. And as the expression says, "Nothing is more expensive than a cheap Mercedes".
Thanks for all the info, I'll look into it more when I have time later in the day. I think I got it for cheap seeing that it runs and drives.
The plastic tube sources from the back of the intake manifold, then routes into the passenger side fender well, then back out of the fender well into the interior HVAC system. It is the vacuum source for the flapper valves under the dash.
The missing connector on the EGR valve appears to be a sensor according the parts list; the connector wires route into the fuel injector harness fastened to the fuel rail on the passenger side.
When repairing the wires, I recommend inserting a new piece of wire long enough (6-8"?) to easily manipulate and make a service loop to take up the extra length; makes it much easier to repair the harness if you go that route. Heat shrink tubing over the wire, twist wires for a good mechanical connection, solder and then shrink the tubing over the solder joint. EDIT: looking at the video, it appears you used a crimp butt connector to repair at least one wire. That is guaranteed to be a failure point now or later. Do it correctly the first time or you will be doing it again later and usually at the most inopportune time.
HVAC issues can be identified by reading the codes directly off of the AC control panel; an internet search will find multiple threads explaining how to do so.
WIS schematics would help you to identify what those three wires should be attached to.
Front fans, only one is driven by an electric motor that is controlled by a fan control module (located under the passenger side front fender attached to the frame). The second fan is driven by the first fan via a small v-belt.
I hope you got this car really cheap. And as the expression says, "Nothing is more expensive than a cheap Mercedes".
do you know if Benz ninja can fix this, I’ve seen some threads of him in the forums. And what would it cost
