Transmission Reset Gone Wrong?
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2004 c240 2004 ml350
Transmission Reset Gone Wrong?
Hello everyone. My first post. I need HELP!! I tried the TCU reset procedure today on my Girlfriends 2004 c240 4matic.
1) Got in the car (without remote/alarm fuse was blown at the time)
2) Turned key to ON position (just before start) all dash lights on
3) Floored it, depressing the button under pedal for 30 SECONDS
4) Holding down pedal, turned key to OFF
5) Released pedal and waited, touching nothing for 5 MINUTES
6) Took out the key and exited the car
Then I went I waited for my Girlfriend to come outside (30 minutes or so) She tried to start the car and it won't start and she won't stop crying. Hence my username...
Dashboard lights up like normal ( with usual turn signal malfunction warning), turns over/cranks but won't start...
I tried the procedure twice...Tried restarting it numerous times after an hour or so, while giving it gas and not giving it gas..
I replaced the Fuel pump relay just in case, Fuel pump fuse was fine.
Tried flooring it during cranking for 10 seconds or so..
NOTHING.....
Could I have flooded the fuel-injected system somehow? If so, how long should I wait, or what should I do?
Could a botched procedure cause the car, that was starting fine, to not start?
Could the alarm fuse or turn signal malfunction played a role in botching the procedure?
Or am I just a bad boyfriend? Help..
1) Got in the car (without remote/alarm fuse was blown at the time)
2) Turned key to ON position (just before start) all dash lights on
3) Floored it, depressing the button under pedal for 30 SECONDS
4) Holding down pedal, turned key to OFF
5) Released pedal and waited, touching nothing for 5 MINUTES
6) Took out the key and exited the car
Then I went I waited for my Girlfriend to come outside (30 minutes or so) She tried to start the car and it won't start and she won't stop crying. Hence my username...
Dashboard lights up like normal ( with usual turn signal malfunction warning), turns over/cranks but won't start...
I tried the procedure twice...Tried restarting it numerous times after an hour or so, while giving it gas and not giving it gas..
I replaced the Fuel pump relay just in case, Fuel pump fuse was fine.
Tried flooring it during cranking for 10 seconds or so..
NOTHING.....
Could I have flooded the fuel-injected system somehow? If so, how long should I wait, or what should I do?
Could a botched procedure cause the car, that was starting fine, to not start?
Could the alarm fuse or turn signal malfunction played a role in botching the procedure?
Or am I just a bad boyfriend? Help..
Thread Starter
Newbie
Joined: Oct 2017
Posts: 4
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2004 c240 2004 ml350
Hi. I disconnected the battery while running up to the parts store for the fuel pump relay. Was disconnected for 40 minutes or so..
Is that long enough?
Is this a suggestion to clear the computer of any bad info?
I'm praying I didn't ruin her computer system..I'm heading back to the car this morning in hopes that it was flooded and will start today..
I've read to try starting it in Neutral...or disconnecting battery cables and holding them together to reset computer, then try to start....
Fingers crossed..
Is that long enough?
Is this a suggestion to clear the computer of any bad info?
I'm praying I didn't ruin her computer system..I'm heading back to the car this morning in hopes that it was flooded and will start today..
I've read to try starting it in Neutral...or disconnecting battery cables and holding them together to reset computer, then try to start....
Fingers crossed..
Thread Starter
Newbie
Joined: Oct 2017
Posts: 4
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2004 c240 2004 ml350
Load test showed that the battery was weak. Replaced battery, same problem. Tried a forced Neutral start. Nothing. It feels fuel related, but the coincidence of the transmission reset attempt, still concerns me and seems impossible that it's not somehow related.
Tomorrow I will test to hear if the fuel pump turns on when ignition is engaged. And then start changing spark plugs. I'm at a loss. Could this transmission reset procedure cause damage if done wrong, or to the wrong car? Someone correct me if I'm wrong but a 2004 c240 4matic is a 722.6 right?
This reset procedure should either work or do nothing, correct? Does anybody know WHAT EXACTLY does resetting the TCU affect, component-wise? Does it affect the fuel or starting system??? AND could a faulty #8 fuse (keeps blowing, once I put new fuse in) affect this transmission reset procedure or start up?
Tomorrow I will test to hear if the fuel pump turns on when ignition is engaged. And then start changing spark plugs. I'm at a loss. Could this transmission reset procedure cause damage if done wrong, or to the wrong car? Someone correct me if I'm wrong but a 2004 c240 4matic is a 722.6 right?
This reset procedure should either work or do nothing, correct? Does anybody know WHAT EXACTLY does resetting the TCU affect, component-wise? Does it affect the fuel or starting system??? AND could a faulty #8 fuse (keeps blowing, once I put new fuse in) affect this transmission reset procedure or start up?
Thread Starter
Newbie
Joined: Oct 2017
Posts: 4
Likes: 0
2004 c240 2004 ml350
UPDATE: Checked voltage @fuel sending unit's 5-pin connector. Brown is ground, Black/Green is +12volts when relay is activated (key ON) No noise from fuel pump. No pressure in fuel rails.
THE STRANGE THING IS.....as soon as I turn key to ON, I get around 12v @Black/Green, then it immediately drops back to 0v......If I turn key to START, voltage goes back up to 12v but the car nor the fuel pump start.....
I tried using a fused(20a) jumper straight from the POSITIVE terminal of the battery, stripped a bit of the Black/Green wire at the 5-pin. Alligator clipped onto my visible bare Black/Green wire and with the 5-pin plugged in (using Ground W18) still got no start.
So,,,with constant 12v at the 5-pin on top of the Sending unit and using it's specific Ground circuit, which I checked for continuity, still no start!!!!!??????
Fuel Pump or ECU?
PS-fuel pump relay socket tested at 3.5volts from ECU(key ON), Constant 12v from terminal 30, Switched 12v(key ON) and Continuity from terminal 87 to Fuel sending unit.
Even replaced the relay to be sure...HELP!
THE STRANGE THING IS.....as soon as I turn key to ON, I get around 12v @Black/Green, then it immediately drops back to 0v......If I turn key to START, voltage goes back up to 12v but the car nor the fuel pump start.....
I tried using a fused(20a) jumper straight from the POSITIVE terminal of the battery, stripped a bit of the Black/Green wire at the 5-pin. Alligator clipped onto my visible bare Black/Green wire and with the 5-pin plugged in (using Ground W18) still got no start.
So,,,with constant 12v at the 5-pin on top of the Sending unit and using it's specific Ground circuit, which I checked for continuity, still no start!!!!!??????
Fuel Pump or ECU?
PS-fuel pump relay socket tested at 3.5volts from ECU(key ON), Constant 12v from terminal 30, Switched 12v(key ON) and Continuity from terminal 87 to Fuel sending unit.
Even replaced the relay to be sure...HELP!
