dosnt start on megasquirt AND I NEED IT ON MONDAY FOR SCHOOL!!

[Sundance 6g72]

as you guys know, i had been daily driving my car on megasquirt

i changed nothing to the tune and did not mess with the wiring. I had the battery unplugged for a week or two now but the car is fixed (so i think, id like to start it and find out) but the MS does not turn on

-wont register in tuner studio
-coil does not get power (via my test light)
-pump does not prime.

i switch over to stock computer and it started right up BUT stalled due to my huge injectors and the fact that my 93 ecu is sequential and ms is batch (my injectors are wired into 2 groups of 3 and stock ecu does not like that.. i wonder if running an older ecu would let me run batch injection instead


anyways, why is ms not turning on? i hardwired it to the battery and that did nothing.

the ground strap on the passenger side motor mount was removed and i dont know where to attach it so i ground the top of the mount so it was bare metal and put the ground strap on there. still no difference


now remember i did not touch any of the wiring when i was timing the car.. the wiring is on the driverside and out of the way anyways. i cant run the stock ecu anymore either due to the gm coolant temp sensor and the batch wired injectors. i plan on deleting the stock ecu soon BUT it did start on stock ecu so this makes me think that all the relays and such are correct (my ms is tapped into the factory harness)

[Sundance 6g72]

long story short, the car sat for 2 weeks with the battery disconnected and now the MS wont turn on

after a Google search, im not the only one with this problem

[Sundance 6g72]

only wires i unplugged where the alternator harness, tps, coolant temp, iat. kept dizzy plugged in. as far as i know, i plugged those wires back in correctly.

[Aries_Turbo]

reflash the chip with the boot jumper thing?

---------- Post added at 03:53 PM ---------- Previous post was at 03:52 PM ----------

ms2 or ms1?

what version board?

[Ondonti]

Have you confirmed 12v is going to the megasquirt and that the ground wire is functional? Fuse not blown. Gotta start with telling us the basics.

[Sundance 6g72]

Well the power wire is tapped into the power wire that powers the stock ecu. Same with the grounds.. they are tapped into the factory grounds.

Ryan and I talked about wiring it like this and he seemed to think it was fine.. and it did run fine and always worked until i let it sit for 2 weeks with the battery unplugged

edit: basically if the car starts on stock ecu, then the grounds and power wires should be 100% correct for megasquirt..

[Sundance 6g72]

reflash the chip with the boot jumper thing?

---------- Post added at 03:53 PM ---------- Previous post was at 03:52 PM ----------

ms2 or ms1?

what version board?

version 2.1 i think but i cant remember. ill have to ask ed because i need the same version as him. its MS2 obviously and im not sure about reflashing with the jumpers as i dont know how to even do that... especially if the unit does not power up (as far as i know)

[Shadow24]

green PCB or Blue? I'm betting you have an MS2 with either a V3 or V3.57 board (blue PCB). you sure you didn't pop a fuse when you reconnected the battery? (you DO have a fuse on the main power to the MS right....?)

Don't assume ANYTHING works and start checking from square 1 with a DVOM, ground ohms out OK, power has +12v etc. if its not turning on, not priming the pump or cycling the injectors, the MS does not have power or ground for some reason. heck it could be as simple as a local rodent thought one of your wires was tasty =shrug= or who knows what.

Biggest thing for the MS is GOOD GROUNDS. MS sinks 90% of everything to ground so if you have bad grounds, you'll have issues.

[c2xejk]

Have you taken the cover off and probed for 12v yet? Also look for black spots (burned components...)

[Sundance 6g72]

havnt checked for 12volts and there is no black spots. the board looks fine

and yes i have msII blue pcb board v3.57

no fuse for the power that i know of.. i just wired the MS power wire into the power for for the sbec.. that should be fused though, let me check my diagrams


the only diagnostics i have done are put a test light on the MS power wire.. the light lit up when i turned the key on, so ms is getting power. i then took the 3 ground wires that i am using for MS ground and wired them directly to the battery. still no change. so im getting power and i have a good ground yet nothing works

now guys remember, my power and grounds are the same as my sbec.. and the sbec starts the car on a dime.. just dosnt run good because of the big injectors and wrong cts.

now the only wiring that i changed was the crappy ground strap that was hooked to the passenger side motor mount. I dont know where to hook this up so i ground a spot on the mount and attached it.

my problem seems to be similar to this guys

http://forums.vwvortex.com/showthread.php?3246175-Megasquirt-ECU-not-turning-on...

basically his power cable came off, he popped a fuse. now his ECU gets power but does not turn on.

as far as rodents chewing wires, they look fine and again, the sbec starts the car which verifies power and ground

[Shadow24]

if he popped a fuse, he spike the power side of the electrical system which is BAD. Also the reason the other forum members were having him diagnose the power supply side of the MS. This is also why I run a relay board so spikes WON'T fry the MS. At this point, I'd take a DVOM and go through the power supply troubleshooting of the MS as mentioned in your link above after checking that you are getting 12V to the MS an that the grounds don't have high resistance between the MS and the ground/battery.

And please, I've one a fair bit of gremlin chasing on my MS wired car; ASSUME NOTHING!!!! Assuming something is or isn't working will have you chasing your tail for way to long than taking the time to do a few checks to ensure no bad connections etc.

[Sundance 6g72]

i mine as well re wire the car with the sbec crap removed. that would make checking wires so much easier.. i mine as well to sense i cant run with the sbec anymore. it was nice when i could switch back in forth with my stock injectors and clt.

anywho, ill re read that link. not sure what a dvom is but ill look it up.. im probably just not thinking. i need to get ahold of a multimeter as well.

[Shadow24]

DVOM = Digital Volt Ohm Meter

Probably want to read the section they reference of the assembly of the power circuit on the v3.0 board and the troubleshooting. May also want to post up on msefi.com forum for some input as well

[Sundance 6g72]

i dont have a "stimulator"

not sure how that works, ill have to look into it

[glhs0426]

Without a "stimulator" you will have to use the DVOM (multimeter) directly on the board to check the power supply. I use T pins clipped to the wires of my DVOM when checking the board.

You mentioned the switched power and grounds, but you did not mention anything about checking power inside the MS2. Unplug the MS2 and verify B+ (battery voltage) on pin 28 when the key is switched on. Verify low resistance to ground on pins 7-11. Anything higher than 5.0 Ohms is definately a bad ground. If those are good you will have to get out the PCB diagrams and trace the output of the board power supply (5 volts) to the MS chip. Pin 19 should be sensor ground. If it is tied into pins 7-11 bad things can happen (overheat, power supply failures, irratic idle, mysterious resets, etc.)

After you get this going you should build a backup immediately and carry it in the car. If this is your only mode of transportation you should safeguard yourself from this happening next time.

[Sundance 6g72]

i used pins 17-19 for my sensor grounds. pin 7-9 are my megasquirt ground wires. I have all 3 MS ground wires tied into the factory ground wires for the sbec (pin 11 and 12 on the 93 v6 sbec) These two wires go straight to the battery but before they get to the battery. Now, after looking at the sbec wiring diagram, the sensor ground wires intersect with the main ground wires.

I used the sbec sensor ground wires for my MS sensor grounds. So basically before pins 7-9 get to the battery they meat up with pins 17-19. Maybe this is the issue? should i wire pins 7-9 directly to the neg battery terminal? The car ran just fine with this setup. i have not touched those wires.. not sure why they would decide to give me an issue

now this is what i think is most probable.. sense i used the factory wireing, i ASSUMED that the ignition power wire (pin 9 on sbec) was fused. I wired the MS power wire into this wire as it only gives power when the car is on. I did not install a 2amp fuse.. and the MS wiring diagram says i need a 2amp fuse

i think i blew something in the MS and i cant find it

[Aries_Turbo]

sometimes with power issues, you can blow the chip that drives the larger injector drivers.

happened to a friend of mine with a MS.

as for the boot jumper, if something wiped the MS2 chip memory (a fluke), there is a jumper on the MS2 daughter card itself that allows a rescue boot i think.

you also have to use that to go to a different codebase like 3.1 extra or anything like that.

Brian

[Sundance 6g72]

the H1 jumper and yes its labeled boot.

i tried using that to re flash it earlier today but no luck. i really think its just not turning on but like others said, i need to verify power inside the MS


when i look at the board, all i see is Greek. i dont understand a damn thing

[Ondonti]

Well first check power at the connector (remove it). and if you didn't run a fuse..........

[Sundance 6g72]

if you didnt use a fuse, your Fed!

finished it for you

how do i remove the connector? im assuming its the one where the ms harness plugs into

[87turbodance]

Have you checked for 12V and 5v at the voltage regulator? What board version do you have again? The 3.0 or the 3.57?

I have never experienced a failure with Ms from leaving my car sit for an extended period of time.

[Ondonti]

I am talking about where the harness plugs into MS. Start from the most simple check point. Check the ground there too. Then move on to the board if you have power and ground at that spot.

Mine sat for 5 months and fired up.

[Sundance 6g72]

I am talking about where the harness plugs into MS. Start from the most simple check point. Check the ground there too. Then move on to the board if you have power and ground at that spot.

Mine sat for 5 months and fired up.

so probe the power and ground pins with a multi meter?


Have you checked for 12V and 5v at the voltage regulator? What board version do you have again? The 3.0 or the 3.57?

I have never experienced a failure with Ms from leaving my car sit for an extended period of time.

3.57. and by voltage regulator do you mean the 12v input pin and the 5v output pin?

[87turbodance]

On the board you can measure for power at U5 which is the component mounted on the heat sink near the db9 serial connector.
The center pin is ground and you need to measure for +12v on the left pin and +5v on the right pin.

I bet that something has gone wrong with the wiring leading to MS and not MS its self.

Check for power at the harness leading to MS as Ondonti suggested.

[Sundance 6g72]

On the board you can measure for power at U5 which is the component mounted on the heat sink near the db9 serial connector.
The center pin is ground and you need to measure for +12v on the left pin and +5v on the right pin.

I bet that something has gone wrong with the wiring leading to MS and not MS its self.

Check for power at the harness leading to MS as Ondonti suggested.

So take the NEG probe and put it on the center pin and then take the pos probe and check the left pin for 12v and the right pin for 5v.

I checked for power going to the MS power wire.. brent made me think i should be checking the connector its self with the harness removed. Ill see what i can do.



My fuel pump and coil are not priming when the key is turned.. this made me think that my fuel pump output wire (on the MS harness) is not connected right. This wire is the one responsible for turning the ASD relay on, and that is what powers the fuel pump and coil. I verified that the pump and coil work by starting the car with the stock computer. So for some reason, power must not be leaving the fuel pump output wire on the MS harness.

[Sundance 6g72]

did some testing, this is what the tech at diy told me to do


That's too bad--the stim would be an easy and fast way to rule in and
rule out problems.

It still sounds to me like there's a problem in the wiring. One of the
telling signs is that you said your coil is not getting 12v with the
MegaSquirt. Well the coil is not powered through the MegaSquirt. I
would check over the power wiring that powers up the MegaSquirt and the
coil. Something isn't right somewhere.

To check for a short in the Megasquirt PCB, power up the Megasquirt on a
Stimulator or on the car and check the following points for voltage with
a multimeter.

You should find the same voltage as the battery voltage on the following
points: S12, S12C, the center legs of Q9 and Q12, the left (non-banded)
end of D3, the left leg of U5, and the left (banded) end of D9.

You should have 5 volts at the following points: S5, the two +5V holes
in the proto area, the right (non-banded) end of D9, the right leg of
U5, the left (banded) end of D19, and pins 1, 20, and 31 of the CPU.

Let me know where you find the correct voltages, and where you find the
wrong ones. Once you get back to me with the measurements, I'll send you
the next thing to check based on what you find.


Thanks,

Ben Berusch
DIYAutoTune.com Technical Support

Please quote your message when you reply. This will help me look up our conversation and reply faster, as I'm usually assisting multiple customers.

these are my results and what i sent to the tech


okay did some testing and from what i know, it all looked good


battery voltage was a little above `12volts and i got the following readings when setting my craftsmen voltage meter to the DC - 20 setting.. not sure if that was correct but it gave me the right battery reading so i figured it was okay.


Q12, from left to right 11volts, 11.79v, 11.45 volts.


U5. left pin 10.92v, right pin 5volts


D3 both sides showed 11.26volts min. i think the max was 11.85.. it fluctuated if my hand was not steady


D6 right side was 11.35volts


5v holes. 1 had a pin, the pin read 4.75 volts, the second hole read 4.85volts


D9 right side 4.85v


What i thought was D19 4.75v THE reason i say i think its d19 is because i could not find d19 and this was the only "d" where the first number was "1" and the second was blocked because a hole was in its spot.. like the 5volt hole. This piece was to the left of d22 and right under r31.



CPU pins. This got tricky because i was not sure how to count the pins out. im assuming1 and 21 are in the corners. all 4 corners ready out 4.85- 4.75volts.
pin 31 was more difficult to find. I counted from the top of the cpu (by chip c13, r11, c17) and went down. first i did the left side pins and going from 21 and downward, i hit 31 and read out 4.88volts. If i counted on the right side going down starting at 21, pin "31" would read nothing. Same thing if i went fromt he bottom up starting at 21 on both sides, i would get 0volts. So i hope i did it right the first time but im still unsure on how to find pin 31. I hope that makes sense.

[Sundance 6g72]

power is deff going from the MS pin 37 to the asd relay

pin 37 is turned on when the key is turned to the on position, effectively tuning the asd on.. which in turn turns the pump on. problem is, the pump never comes on. I know the wiring between the asd to the fuel pump relay is right because the factory ecu turns the pump on just fine.. and does this by powering the asd.

my first assumption would be that the grounds are wrong on the MS.. i verified that the ms ground wires for MS ground and sensor ground are correct and making contact with the factory ground wires.

there is also the fact that the laptop does not see the MS anymore.. i guess i cant try again but i dont think its outputting power through the cable. maybe i can probe the DB9 pins tomorrow

if only i had a stimulator

[Sundance 6g72]

s12 and s12c both had 8.4 volts BUT my battery voltage is now down to 9. something

[Ondonti]

Keep it on a charger or you will start chasing more problems.