Thumper Posted November 16, 2005 Share Posted November 16, 2005 I have all my sensors connected to megasquirt. I know it is getting 12volts and ground. When I turn the car on all the sensors get the appropiate voltage, TPS 5v, IAT 3v, exc... The problem is when I turn the car on the led next to the db9 connection flashes for a split second. After that nothing. No light during trying to start and no solid lights. I also cannot connect to the ecu via my labtop using megatune. Any suggestions? Thanks Quote Link to comment Share on other sites More sharing options...
oinojo Posted November 16, 2005 Share Posted November 16, 2005 i had the same problem and i decided to start over with the wiring... im waiting on my ignition module and havent tried since. I would get the red (warmup) light on for like 2 seconds then it turn off. I couldnt even connect to it with the laptop. Quote Link to comment Share on other sites More sharing options...
Thumper Posted November 16, 2005 Author Share Posted November 16, 2005 Well I don't even get the warmup light. I just get a .3 seconds flash Quote Link to comment Share on other sites More sharing options...
midnightzxt Posted November 16, 2005 Share Posted November 16, 2005 maybe you're not getting a tach signal? The injectors and the spark wouldn't be told to fire if you're not getting a tach signal. Try hitting the tps quick and see if the right led lights up. Quote Link to comment Share on other sites More sharing options...
Thumper Posted November 17, 2005 Author Share Posted November 17, 2005 Update: It gets power and ground. It sends out power to all the sensors. D17 led flashes for a split second when car is turned on. No other lights light up. My new question is will the led d17 flash during cranking if I haven't load a map yet? Because I have not been able to connect my labtop to the ecu yet. It might be the labtop though that is causing the problem in communication. Also why would tapping the tps make the led light up? Thanks Quote Link to comment Share on other sites More sharing options...
Thumper Posted November 17, 2005 Author Share Posted November 17, 2005 One other thing I just found out that pin 19 is not grounded. The builder said this is not necessary? I am not running a relay board I have all my sensors grounding to chassis at the same location of the megasquirt. Is this a problem? Thanks Quote Link to comment Share on other sites More sharing options...
Thumper Posted November 17, 2005 Author Share Posted November 17, 2005 Sorry forget to tell you what i'm running. Megasquirt 2.2, with msns-extra 25v2. With megatune b656. Quote Link to comment Share on other sites More sharing options...
mario_82_ZXT Posted November 17, 2005 Share Posted November 17, 2005 One of the best ways to test the MS ECU is to get a stim, a DVM, and run the tests in the assembly manual. The serial communications section might be inadequately soldered. Mario Quote Link to comment Share on other sites More sharing options...
Thumper Posted November 17, 2005 Author Share Posted November 17, 2005 Well I have tried with two different labtops and two different types of connectors one db9 to db9 and one db9 to usb and non of these work. So I think it is ms. One of the reasons I bought a preassembled unit is so that I wouldn't have to buy a stim. I know that the blue/tach wire is receiveing a 12v signal from the distributor. I know that pin 19 is not grounded. I know that the led closest to the db9 lights up a for a split second when the car is turned on, then no lights, I know that I cannot connect to the ms box via megatune. What does this mean bad MS box or some wire I messed up? Thanks Quote Link to comment Share on other sites More sharing options...
Tony D Posted November 17, 2005 Share Posted November 17, 2005 "One of the reasons I bought a preassembled unit is so that I wouldn't have to buy a stim." Well, now you see FIRSTHAND why most people who built their own units tell everyone to buy a Stim! It's the ONLY thing that will tell you in about 30 seconds or less, if your BOX is bad, or if it's SOMETHING ELSE! Bet you would kill about right now to KNOW... Quote Link to comment Share on other sites More sharing options...
Metro Posted November 17, 2005 Share Posted November 17, 2005 Update: It gets power and ground. It sends out power to all the sensors. D17 led flashes for a split second when car is turned on. No other lights light up. My new question is will the led d17 flash during cranking if I haven't load a map yet? Because I have not been able to connect my labtop to the ecu yet. It might be the labtop though that is causing the problem in communication. Also why would tapping the tps make the led light up? Thanks If your MS is wired up without using any of the LEDs to drive spark, D17 is injector pulse. The initial flash is the priming pulse. If you don't have a fuel map setup, I don't think MS will fire the injectors at all - so no flash. Just load up the default v8 setup, it should flash when cranking. What midnightzxt suggested is that you blip the throttle when it's cranking. The middle light is accel enrichment and it should turn on/off quickly. But if you can't connect to the ecu, this is all pointless, you really need to solve that first. You might think it's wired correctly, but who knows if you can't see what the sensors are reading. Quote Link to comment Share on other sites More sharing options...
Thumper Posted November 17, 2005 Author Share Posted November 17, 2005 Well after much fun I have found out somethiing IS wrong with the ms box. I am sending it back tomorrow and he is going to repair it. My friend is going to let me use his ms 2.2 Only thing is I need to upgrade it from msns to msns-extra. Should be oh so much fun. ThanksI do have a problem with my input though but thats for another thread. Quote Link to comment Share on other sites More sharing options...
mobythevan Posted November 17, 2005 Share Posted November 17, 2005 Just like network cables there are two types of db9 cables, if you are grabbing some that are laying around from the office or from your home PC setup. There are straight through types and crossover types. Make sure you have the right type, measure with a multi meter to verify the pinout on both ends of the cable. Megamanual should explain this, but I didn't go look. I went through about 20 cables here at work and only found 2 that were the correct style to work with megasquirt. I don't remember off hand which one is correct, check the megmanual. Quote Link to comment Share on other sites More sharing options...
mobythevan Posted November 17, 2005 Share Posted November 17, 2005 Here is the info on the DB9 cable from msefi.com 3. Your DB-9 cable must be a strait pass through cable, not a null modem cable. So pin1 must be connected to pin 1 on both ends, on down through all the pins. Quote Link to comment Share on other sites More sharing options...
Thumper Posted November 17, 2005 Author Share Posted November 17, 2005 Yes it was a straight-thru. And I installed my friends 2.2 board and everything works perfectly so it was my box. Thanks Quote Link to comment Share on other sites More sharing options...
oinojo Posted November 18, 2005 Share Posted November 18, 2005 when the car is on the (on) position... is the megasquirt unit supposed to have any lights on? I dont have a stim or anyone else with a megasquirt i know of around my area so i dont know what its supposed to do before cranking. My megasquirt unit is getting 12v to the wiring harness but i cant tell if its the box or if its my connection to the unit. I bought a serial cable from diyautotune.com so i know its straight thru. When i have the key on (on) the MS warmup light lights for about 3 seconds then turns off. Is this normal? Quote Link to comment Share on other sites More sharing options...
Metro Posted November 19, 2005 Share Posted November 19, 2005 when the car is on the (on) position... is the megasquirt unit supposed to have any lights on? I dont have a stim or anyone else with a megasquirt i know of around my area so i dont know what its supposed to do before cranking. My megasquirt unit is getting 12v to the wiring harness but i cant tell if its the box or if its my connection to the unit. I bought a serial cable from diyautotune.com so i know its straight thru. When i have the key on (on) the MS warmup light lights for about 3 seconds then turns off. Is this normal? I don't think it's normal. When I turn mine on, I get a quick blip from the injector LED showing the ecu firing the priming pulse and that's it. Quote Link to comment Share on other sites More sharing options...
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