can I use a 1996 ecm with my 1999?
07-03-2009, 05:50 PM
#1
can I use a 1996 ecm with my 1999?
I tried searching but could not find an answer. So please don't flame.
I think my ecm is fried. I got a 1996 ecm laying around somewhere, will that work on my 1999? theyre both manual transmission ecm's...
thanks
I think my ecm is fried. I got a 1996 ecm laying around somewhere, will that work on my 1999? theyre both manual transmission ecm's...
thanks
07-03-2009, 07:09 PM
#4
oh i belive there is more to it then that. i know the CKPS(REF) is pin 46 on the 99 and not pin 44. Im sure there is more that differ as well.
Im sure pmohr will chime in and set the record straight
Last edited by Product_Of_Korea; 07-03-2009 at 07:13 PM.
07-04-2009, 09:34 AM
#7
IIWM, I'd get pix of the 99' pinout and the 96' pinout and compare. Pmohr has linx to the FSM's, just pdf dox .... open a couple of browsers and open the 96 FSM and the 99 FSM. I think you'll find that you will have several changes to make. I understand using parts already in hand, but how much would a 'new' 99' ECU cost? Might only be a few bucks (~$45 or so????) I had to replace an ECU in a 91' Max that I had a while back and I found a used one for $45 online, $10 shipping - $55 and no cutting / splicing of wires.
07-04-2009, 09:41 AM
#8
IIWM, I'd get pix of the 99' pinout and the 96' pinout and compare. Pmohr has linx to the FSM's, just pdf dox .... open a couple of browsers and open the 96 FSM and the 99 FSM. I think you'll find that you will have several changes to make. I understand using parts already in hand, but how much would a 'new' 99' ECU cost? Might only be a few bucks (~$45 or so????) I had to replace an ECU in a 91' Max that I had a while back and I found a used one for $45 online, $10 shipping - $55 and no cutting / splicing of wires.
If I can get someone to give me concrete pinout details, I'll make a correct pinout and add it to http://forums.maxima.org/all-motor/5...0-px-wide.html
Also with getting a '99 ECU, you'd have to have it reprogrammed to accept the current keys. Granted, some may like the immobilizer system, personally I think it's just a PITA.
07-04-2009, 09:44 AM
#9
The '99 FSM pinout is incorrect, which is the issue.
If I can get someone to give me concrete pinout details, I'll make a correct pinout and add it to http://forums.maxima.org/all-motor/5...0-px-wide.html
Also with getting a '99 ECU, you'd have to have it reprogrammed to accept the current keys. Granted, some may like the immobilizer system, personally I think it's just a PITA.
If I can get someone to give me concrete pinout details, I'll make a correct pinout and add it to http://forums.maxima.org/all-motor/5...0-px-wide.html
Also with getting a '99 ECU, you'd have to have it reprogrammed to accept the current keys. Granted, some may like the immobilizer system, personally I think it's just a PITA.
Muhbadddd
07-04-2009, 09:47 AM
#10
And to think, I had a nearly complete '99 harness sitting here for the longest time, I didn't even think about testing the pinout myself before I had hacked the thing up.
Now it's a pile of connector pigtails and a few rolls of wire, sectioned by color.
Now it's a pile of connector pigtails and a few rolls of wire, sectioned by color.
07-04-2009, 11:11 AM
#12
Yeah 99 is the screwy year.
Hell im running a 97 auto ecu in my 96 5speed with no drivablity problems at all W\ a EU wired in. I just throw a code for not having a TCU
OP: FWIW i would just go with a 99 ECU. Im sure they are just 10-20 dollars more than your 95-98 ecu's and you dont have to mess with rewiring half your ECU(Its not fun belive me). But then again like said earlier you would have to reprogram for the immobilizer. but on the flip side i couldnt even imagine getting the immobilzer to work on 95-98 ecu's.
Hell im running a 97 auto ecu in my 96 5speed with no drivablity problems at all W\ a EU wired in. I just throw a code for not having a TCU
OP: FWIW i would just go with a 99 ECU. Im sure they are just 10-20 dollars more than your 95-98 ecu's and you dont have to mess with rewiring half your ECU(Its not fun belive me). But then again like said earlier you would have to reprogram for the immobilizer. but on the flip side i couldnt even imagine getting the immobilzer to work on 95-98 ecu's.
07-04-2009, 11:13 AM
#13
Yeah 99 is the screwy year.
Hell im running a 97 auto ecu in my 96 5speed with no drivablity problems at all W\ a EU wired in. I just throw a code for not having a TCU
OP: FWIW i would just go with a 99 ECU. Im sure they are just 10-20 dollars more than your 95-98 ecu's and you dont have to mess with rewiring half your ECU(Its not fun belive me). But then again like said earlier you would have to reprogram for the immobilizer. but on the flip side i couldnt even imagine getting the immobilzer to work on 95-98 ecu's.
Hell im running a 97 auto ecu in my 96 5speed with no drivablity problems at all W\ a EU wired in. I just throw a code for not having a TCU
OP: FWIW i would just go with a 99 ECU. Im sure they are just 10-20 dollars more than your 95-98 ecu's and you dont have to mess with rewiring half your ECU(Its not fun belive me). But then again like said earlier you would have to reprogram for the immobilizer. but on the flip side i couldnt even imagine getting the immobilzer to work on 95-98 ecu's.
07-04-2009, 11:41 AM
#14
Thats what i figured. Even on a 99 i hear its a PITA i couldnt imagine on a non immobilizer ECU.
Glad ive never had to mess with a 99...........
OP: ive seen some 99 ecu's for sale on car-part.com for around 75 bucks
Last edited by Product_Of_Korea; 07-04-2009 at 11:44 AM.
07-04-2009, 10:43 PM
#15
Senior Member
Join Date: Nov 2007
Location: North Coast NSW, Australia
Posts: 217
07-04-2009, 10:44 PM
#16
It's all available in the FSM (in better detail), anyway.
07-06-2009, 09:02 PM
#17
Well Thanks for the help I think I fried my ecu and cant find one for a 1999 mt anywhere dealer quoted $1200 + 250 labor 
...can't afford that now, nor would I pay that much. My injectors seem to stay open after I turn my car off, and my spark plugs keep igniting kind of like dieseling but it does not stop until I either put it into gear, or stap the gas pedal...
Any clues?
...can't afford that now, nor would I pay that much. My injectors seem to stay open after I turn my car off, and my spark plugs keep igniting kind of like dieseling but it does not stop until I either put it into gear, or stap the gas pedal...Any clues?
07-06-2009, 09:51 PM
#18
Senior Member
Join Date: Nov 2007
Location: North Coast NSW, Australia
Posts: 217
07-06-2009, 09:52 PM
#19
07-07-2009, 03:39 AM
#20
Well Thanks for the help I think I fried my ecu and cant find one for a 1999 mt anywhere dealer quoted $1200 + 250 labor ...can't afford that now, nor would I pay that much. My injectors seem to stay open after I turn my car off, and my spark plugs keep igniting kind of like dieseling but it does not stop until I either put it into gear, or stap the gas pedal...
Any clues?
...can't afford that now, nor would I pay that much. My injectors seem to stay open after I turn my car off, and my spark plugs keep igniting kind of like dieseling but it does not stop until I either put it into gear, or stap the gas pedal...Any clues?
Have you tried car-part.com????
I did a quick search and i see 5 for sale all under 125. Also it doesnt matter what trim you use either. IE you can use one off a gxe or se. Also if you dont care about throwing a code you could use one off a auto as well. They are all pretty much interchangeable(within the 99's)
Also 250 seems kinda steep for just a hour of labor. But then again it is the dealership.....
FWIW the ecu is real easy to change out. Maybe 3 bolts to undo IIRC. Its just not in the most convient spot. But doable with basic tools.
Last edited by Product_Of_Korea; 07-07-2009 at 03:41 AM.
07-07-2009, 02:37 PM
#21
okay, the ecu just slides out of the mounting bracket right? I removed all the screws and it wont come out and its hella hot/humid outside so it was aggravating me so i need to take a break. off to school now I'll try later.
07-07-2009, 02:39 PM
#22
Personally I pull out the center stack (vents, radio, shifter trim, ashtray, etc), then unbolt the two 10mm head bolts that hold the entire bracket in place. Unplug the two or three dash harness connectors, and you should be able to slide the ECU/bracket/wiring harness all out in one shot.
Takes about 10 minutes (your first time, anyway) like that, much easier than ****ing around with the 4 phillips head screws (IMO).
07-07-2009, 06:19 PM
#24
is it uncommon for my ecu to be toast? When I cranked my engine the first time, after installing a new fuel injector, without the REF crankshaft sensor even connected, it just cranked over (I thought I didn't need the CKPS connected anyways, since the ECU threw a faulty REF CKPS code to begin with) and did not ignite/start...
When I connected the REF CKPS just for ****s to see if it would do anything, the engine then fired up, but it stays on after I kill the ignition(not dieseling sinse it keeps chugging away, as if it's continually being fed gas/spark without signal from the ecu).
I checked the harness going to the REF CKPS, and it seems dead, ie: no continuity to ground as the Haynes manual says to check for...but the sensor itself reads 540 or so ohms of resistance, so it cannot be bad...which would mean that the wires going to it are bad since there isn't any continuity, right? And those same wires go directly to the ECU correct?
So my question is after the big rant above, is why would the engine start when I connected the REF CKPS when the wires going to it are not giving it a signal?
When I connected the REF CKPS just for ****s to see if it would do anything, the engine then fired up, but it stays on after I kill the ignition(not dieseling sinse it keeps chugging away, as if it's continually being fed gas/spark without signal from the ecu).
I checked the harness going to the REF CKPS, and it seems dead, ie: no continuity to ground as the Haynes manual says to check for...but the sensor itself reads 540 or so ohms of resistance, so it cannot be bad...which would mean that the wires going to it are bad since there isn't any continuity, right? And those same wires go directly to the ECU correct?
So my question is after the big rant above, is why would the engine start when I connected the REF CKPS when the wires going to it are not giving it a signal?
Last edited by Maximeltman; 07-07-2009 at 06:31 PM.
07-07-2009, 06:26 PM
#25
is it uncommon for my ecu to be toast? When I cranked my engine the first time, after installing a new fuel injector, without the REF crankshaft sensor even connected, it just turned over (I thought I didn't need the CKPS connected anyways, since the ECU threw a faulty CKPS code to begin with) and did not ignite/start...
When I connected the REF CKPS just for ****s to see if it would do anything, the engine then fired up, but it stays on after I kill the ignition(not dieseling sinse it keeps chugging away, as if it's continually being fed gas/spark without signal from the ecu).
I checked the harness going to the REF CKPS, and it seems dead, ie: no continuity to ground as the Haynes manual says to check for...but the sensor itself reads 540 or so ohms of resistance, so it cannot be bad...which would mean that the wires going to it are bad since there isn't any continuity, right? And those same wires go directly to the ECU correct?
So my question is after the big rant above, is why would the engine start when I connected the REF CKPS when the wires going to it are not giving it a signal?
When I connected the REF CKPS just for ****s to see if it would do anything, the engine then fired up, but it stays on after I kill the ignition(not dieseling sinse it keeps chugging away, as if it's continually being fed gas/spark without signal from the ecu).
I checked the harness going to the REF CKPS, and it seems dead, ie: no continuity to ground as the Haynes manual says to check for...but the sensor itself reads 540 or so ohms of resistance, so it cannot be bad...which would mean that the wires going to it are bad since there isn't any continuity, right? And those same wires go directly to the ECU correct?
So my question is after the big rant above, is why would the engine start when I connected the REF CKPS when the wires going to it are not giving it a signal?
The crank sensors are CKPS REF/POS, not CPS; the cam sensor is the CPS.
Also, 'turned over' is generally regarded as starting, not cranking.
Now:
Just because the sensor reads the correct resistance, does NOT mean that it 'cannot be bad'.
Are you sure you checked the correct pin, number 2? Have you checked continuity to the large connector that feeds the CKPS REF/OPSU/rear bank of injectors?
Did you check continuity of the signal wire from the connector at the CKPS back to the ECU, or are you for some reason assuming that it is an open circuit?
Just because the ground is bad doesn't mean the signal circuit is bad; the ground never reaches the ECU. The ECU could still (potentially) receive a signal even with a faulty ground circuit.
Have you checked/cleaned the two ground straps on the front of the LIM yet?
07-07-2009, 06:30 PM
#26
Hey Product of Korea, thank you for investing ur time u 2 pmohr...
I checked the Car-part.com site and did indeed find a 99ecu, cali spec(mine's fed) and not for mt(the guy said it will not work correctly and he does not offer refunds once they're bought they're on a one-way trip he told me)..soo...
The struggle continues with getting the ecu out. I noticed on the electrical pinout on the 96 the REF is connected at pins 44/48...I could use my ohmeter to check what pins are continuous with the REF sensor I guess...
I checked the Car-part.com site and did indeed find a 99ecu, cali spec(mine's fed) and not for mt(the guy said it will not work correctly and he does not offer refunds once they're bought they're on a one-way trip he told me)..soo...
The struggle continues with getting the ecu out. I noticed on the electrical pinout on the 96 the REF is connected at pins 44/48...I could use my ohmeter to check what pins are continuous with the REF sensor I guess...
07-07-2009, 06:31 PM
#27
Hey Product of Korea, thank you for investing ur time u 2 pmohr...
I checked the Car-part.com site and did indeed find a 99ecu, cali spec(mine's fed) and not for mt(the guy said it will not work correctly and he does not offer refunds once they're bought they're on a one-way trip he told me)..soo...
The struggle continues with getting the ecu out. I noticed on the electrical pinout on the 96 the REF is connected at pins 44/48...I could use my ohmeter to check what pins are continuous with the REF sensor I guess...
I checked the Car-part.com site and did indeed find a 99ecu, cali spec(mine's fed) and not for mt(the guy said it will not work correctly and he does not offer refunds once they're bought they're on a one-way trip he told me)..soo...
The struggle continues with getting the ecu out. I noticed on the electrical pinout on the 96 the REF is connected at pins 44/48...I could use my ohmeter to check what pins are continuous with the REF sensor I guess...
07-07-2009, 06:36 PM
#28
First, there's just a terminology problem here, which is going to lead to confusion.
The crank sensors are CKPS REF/POS, not CPS; the cam sensor is the CPS.
Also, 'turned over' is generally regarded as starting, not cranking.
Now:
Just because the sensor reads the correct resistance, does NOT mean that it 'cannot be bad'.
Are you sure you checked the correct pin, number 2? Have you checked continuity to the large connector that feeds the CKPS REF/OPSU/rear bank of injectors?
Did you check continuity of the signal wire from the connector at the CKPS back to the ECU, or are you for some reason assuming that it is an open circuit?
Just because the ground is bad doesn't mean the signal circuit is bad; the ground never reaches the ECU. The ECU could still (potentially) receive a signal even with a faulty ground circuit.
Have you checked/cleaned the two ground straps on the front of the LIM yet?
The crank sensors are CKPS REF/POS, not CPS; the cam sensor is the CPS.
Also, 'turned over' is generally regarded as starting, not cranking.
Now:
Just because the sensor reads the correct resistance, does NOT mean that it 'cannot be bad'.
Are you sure you checked the correct pin, number 2? Have you checked continuity to the large connector that feeds the CKPS REF/OPSU/rear bank of injectors?
Did you check continuity of the signal wire from the connector at the CKPS back to the ECU, or are you for some reason assuming that it is an open circuit?
Just because the ground is bad doesn't mean the signal circuit is bad; the ground never reaches the ECU. The ECU could still (potentially) receive a signal even with a faulty ground circuit.
Have you checked/cleaned the two ground straps on the front of the LIM yet?
The ground straps are the two little wires with the metal loops that connect to the LIM...I think I did.
07-07-2009, 06:59 PM
#30
More than likely your ecu. But you should find what caused it to fry up like that. In my case i was using the 5th gen iacv and one of the pins was bent that caused a short. I should of went with the 5th gen pig tail instead of modifying the 4th gen plug. and yes i made the mistake of putting a another ecu in with out properly figuring out what was causing the problem. Yes yes i know pmohr should of use the 5th gen pigtail......
You should be able to turn your key to the "on" postion and the CEL should be on. If it doesnt come on, your ecu is more than likely shot.
07-07-2009, 07:44 PM
#32
07-08-2009, 04:06 PM
#38
07-08-2009, 04:10 PM
#39
07-08-2009, 04:15 PM
#40