Yea I just picked one up with a warrenty. I would have had it running by now but i had to send a supposedly rebuilt one back as the caps werent replaced and the board was burnt!
1990 Tracker crank no start
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Perhaps a moot point now, but the computer ‘geek’ in my local town was able to replace my caps, test and replace the injector drivers, clean the traces, etc., in my ECU, as well as make a recommendation to run an inline inline fuse in the injector wiring circuit so that, if the injector wires caused more problems, the fuse would blow well before any damage to the ECU. Then again, he was building computers, and not just some guy in an electronics shop.
I'd say you were VERY fortunate, the average computer 'geek' doesn't know how to use a soldering iron - when I started out as a computer tech back in the '70's, the first class I attended taught the use of the oscilloscope - computer repair back then meant troubleshooting to the component and then breaking out the soldering iron to replace the part. Those days are long gone, and todays techs are primarily "card swappers", no soldering required.
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Is your fuel pump working? It’s probably in the fuel tank.
Did you read through the thread before posting your question?
Below is the very first post in the discussion.
I had similar problem and had to replace ECU. $700. ECU is unique to the 1990 tracker. Could see the “fried” areas on the board in ECU before sending it for replacement. Tracker runs fine now. Good luck.
Yea the one I ordered a few days ago was about $525
Because it takes more than a soldering iron to DIAGNOSE and repair an ECU.
Diagnosis is the first step into any sort of repair, and to diagnose the fault requires an in depth understanding of what the device does, you need a way to generate the inputs that the device requires, and a way to test the outputs that the device produces, you need to observe the outputs for all possible combinations of inputs, to make sure that you get the outputs that are expected, and also to ensure that you don't get any undesired outputs.
What inputs - cam & crank position sensors, coolant & intake air temperature sensors, MAF & MAP sensors, throttle position sensor, electrical load sensors, power steering load sensor, air conditioning load sensor, vehicle speed sensor, B1S1 & B1S2 O2 sensors, 5th gear switch, CO adjusting resistor.
What outputs - injector(s) drive, ignitor or COP coil drive, EGR actuator drive, IAC actuator drive, EVAP purge valve drive, throttle position sensor data
I've limited that list to only what can be expect on an 89~98 Vitara/Sidekick (including the Sport), and I have probably missed a few - the list will get longer (a lot longer) if you include more modern vehicles. Folks who do this as a business are going to have constructed some sort of "simulator", and may have several simulators, one per ECU that they service, because connections don't necessarily interchange.
For the "eagle eyed" amongst you, there are probably some inputs & outputs you didn't expect, like that CO adjusting resistor in the input list, it's not fitted in all markets, vehicles with the CO resistor won't have the O2 sensor, and will have different programming - there is no "closed loop" mode, the 5th gear switch is primarily used to control opening & closing of the EGR and the throttle position sensor data in the output list - that goes to the TCU for the four speed automatic. Not all ECUs will use all inputs or have all outputs
Diagnosis is the first step into any sort of repair, and to diagnose the fault requires an in depth understanding of what the device does, you need a way to generate the inputs that the device requires, and a way to test the outputs that the device produces, you need to observe the outputs for all possible combinations of inputs, to make sure that you get the outputs that are expected, and also to ensure that you don't get any undesired outputs.
What inputs - cam & crank position sensors, coolant & intake air temperature sensors, MAF & MAP sensors, throttle position sensor, electrical load sensors, power steering load sensor, air conditioning load sensor, vehicle speed sensor, B1S1 & B1S2 O2 sensors, 5th gear switch, CO adjusting resistor.
What outputs - injector(s) drive, ignitor or COP coil drive, EGR actuator drive, IAC actuator drive, EVAP purge valve drive, throttle position sensor data
I've limited that list to only what can be expect on an 89~98 Vitara/Sidekick (including the Sport), and I have probably missed a few - the list will get longer (a lot longer) if you include more modern vehicles. Folks who do this as a business are going to have constructed some sort of "simulator", and may have several simulators, one per ECU that they service, because connections don't necessarily interchange.
For the "eagle eyed" amongst you, there are probably some inputs & outputs you didn't expect, like that CO adjusting resistor in the input list, it's not fitted in all markets, vehicles with the CO resistor won't have the O2 sensor, and will have different programming - there is no "closed loop" mode, the 5th gear switch is primarily used to control opening & closing of the EGR and the throttle position sensor data in the output list - that goes to the TCU for the four speed automatic. Not all ECUs will use all inputs or have all outputs
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They will still have the resistance on the later "modern" closed loop control but its used with the A /F sensor to provide a known offset for the sensor being used. This is one of the reasons why you cannot just use any sensor that fits the hole
The earlier ecm are in my opinion more fun to dive into in terms of how they operate, more analogue than digital and some of the things they did to solve problems around emissions and get suitable solutions.........those designers had some smarts
Downside, nobody wants to know, they are old, uncommon (now) and time consuming to repair and that's if you can find components.
The earlier ecm are in my opinion more fun to dive into in terms of how they operate, more analogue than digital and some of the things they did to solve problems around emissions and get suitable solutions.........those designers had some smarts
Downside, nobody wants to know, they are old, uncommon (now) and time consuming to repair and that's if you can find components.
My tracker’s in-tank fuel pump had ingested the old “plastic” fuel strainer/screen and quit working. If you use jumper wires from batt to fuel pump wires will it run? I’m to old to understand the computer s—t. New fuel pump and fuel strainer/screen and all has worked since the repair. Not sure I’ve helped but good luck. I too had previously replaced the “fried” ECM.
The pump is working and can be jumped. When I crank it I can hear it. I know fuel is getting to the TB also. I got 8 volts off of my TPS signal wire and 6 volts at wide open throttle and I dont know how thats possible. Gonna assume the throttle pos sensor is FUBAR.
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Where are you checking for voltage? Check both at the TPS, as well as at the ECU connector. The TPS voltage at the ECU connector is meant to be only about 1v, with the key on or the engine running, according to my FSM. Your gray wire should connect on the yellow connector of the ECU.
So, even with the new ECU, you are not getting the pulse with the noid test? Have you tried just running new wires from the ECU to the injector?
So, even with the new ECU, you are not getting the pulse with the noid test? Have you tried just running new wires from the ECU to the injector?
This is something that needs to be investigated, there are either three or four wires to the throttle position sensor (some years have an "idle switch), the other three are the reference voltage (5v), ground (0V) and the "signal" wire (voltage varies with the position of the throttle).
The sensor is nothing more than a variable resistor, the voltage possible on the signal wire cannot exceed the reference 5V, the "extra voltage" would have to come from somewhere, the ECU, a short in the wiring, or an incorrect measurement technique
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