ECU reporting wrong temp, No closed loop

[fixkick]

updated for you . and more later with log curve, plots.
hit keys, Control + F5 (to up date your cache (browser)

http://www.fixkick.com/ECU/temp-sensors.html

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-" ECM sees 68 degC with 270 ohm and 64 deg with 330 ohm resistors plugged to connector instead of ECT.

id wish i had the volts too, so i can discount a bad 5vdc reg inside ECU.
68C(154f) is 270 ohms (actually is 270 5% resistor shows, 154F, so proving the scan tool is OUT TO LUNCH, bad.
64C(147f) is 330

do the volts, if volts matches my table, then the scan tool is FIBBING. (using a wrong cartridge.) (or the software in the cart, is wrong, and mis-identifies your VIN
and uses a non USA car for tables)
possible reasons.
1: ECU 5vdc supply is way too high bad ECU 5vdc reg inside ECU.
2: scan tool bad. (use Rhinomans tool with the USA update) per this post.) The VIN really does matter ! and the tool must match the VIN.

one or the other.

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i have no idea at all how to check version numbers of Tech one, scanner cartridges. (and is complex, i see lots of TSB on this topic old and hard to understand ,not knowing history of tool from 1984 to now)
there is a TSB telling mech how to know the magic date. build dates, 1995.5. this date they switched to OBD2 in USA, (by law) and the scan tool gets this wrong.
(a bug and revision. and a special cable needed on some)
they have a warning about that.
but your car was not made after July 1995, so is OBD1 car.

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i just added my Excel, log plot to the end of my ECT page. Using the internal sum of least squares fit, plot feature to.
here is the results.


with this plot and file. excel.
you can extrapolate up or down, and get volts to.
but at 180F its clear. 300 ohms, and 0.65v it is.
if the scan tool reads wrong, at 0.65v the tool is bad. (why? , ive not a clue)
in 1996 the scan tool only needs report what C temp it saw, it need not do calcs or use tables. thanks to OBD2.
OBD1 can be a pain, as you can see....

but id bet this ECT error has nothing to do with MPG.
i bet.

[fixkick]

i finished scanning the whole EPC (parts cat)
SQ416 and JB416 both use a different 50G01 sensor. alien. year 99 and up. and are 1.6L engines, but uses different EFI parts.
same with all other EFI larger engines.

My curves do match all (28) SE416 world wide and sammi, SJ413 90-95 EFI.
the problem with this scan tool , is you must trust it to read the vin correctly to get it to work right.
some ECU have no VIN stored but have a secret ECU iD inside. (Rhinoman knows this ,extensively, not me)
the Scan tool must be smart enough to know all ECU's, all engines, and all markets. or it will fail.
or
the original documents for the tool might show a chart, telling what cartridges match which engines. world wide.?

If you learn more about Tech1, please share it..
best wishes !

[luigi daniel]

Finally, got the conclusion :
GM cartridges show lower than real CW temp ( 66 deg C / 151 F) whatever Tech1 or Mastertech is used ; this happens with 2 different ECMs ( original one is California 2 doors 33920-59B3 E2T42991 T 4129 A3 US-3AT and the spare is 2 doors Fed 33920-70EB 0 E2T42991 M1 4290C A6 US-3AT)
Suzuki and Asian Imports cartridges show the real CW temp ( 83 degC / 181 F)
All these, with the old ECT installed. Afterwards I have received and installed the Standard Motors TX40T ECT sensor, anyhow.
So, the Tech 1 is OK, it was quite costly to get a Mastertech just to can prove this.
I have subscribed to AllData for both 95 Geo Tracker and for 95 Sidekick and I went through the TSBs, found the ones related to ECMs and Tech 1.
Now that I know all these, I wonder which ECM to leave on the car ? It has came with the California installed and I have bought a Fed afterwards as for spare ( their data, above )
Thanks a lot !

[luigi daniel]

Just checked one thing: the RPO tag shows NF2 so my car is Fed, Tier 2.
I've found installed Calif ECM ! I feel obvious to fit the spare ECM which is Fed - I don't know the difference between them...

[fixkick]

there are usa ECT and rest of world,'types" we have 2 type here 8v. and 16v and both use the same sensor, but in say Europe, lots more types, EFI and Carb.
all other type code engines are illegal here (EPA) never imported, ever. nor tested for smog... so... no wide choice of sensors here, just 1, in these years.


the eCt on all usa cars are the same. calif and fed, for 10 years. Tracker and Sidekick. ( were not talking Grand Vitara's) These 2 cars are SE416s...
the sensors used, say in Europe are different. (and on GV)
the Calif and feD ecu can have different EGR tests. and can be an issue, (code 51 tests)

The Calif cars , use many different parts.... exhaust and header, EGR, ECU tune, and rules for running the silly CEL lamp, (when and how long the CEL self cancels etc)


I'm not sure what GM did but we dont use the -50G01 ECT sensor here... on SE416s (the E means not grand vitara, just vitara with no grand)
The ECU's here all use SE416 sensors... on all G16a/b and not grand vitaras.
the scan tool reads the secret "who am I code in the ECU" and then uses the correct tables. GM messed up.

until 51s show up, both ECU will be happy in your car, (ive even run the A/T ECU on the M/T for a year) no differences...
the ecu's (P/n) varies by transmission and body weight (door counts) and 4wd, the transmission (a/t) uses new rules when in 4wd, and if running ABS. (cancels ABS in 4wd)
the 95 car uses many features and parts, from the older cars, EGR and exhaust. (suzuki didnt want to make 2 cars. in one county just because of C.A.R.B. rules(calif)
the early cars used vacuum to find bead EGR, then CALIF rules , required the EGR thermoproble that lasted until end of 1995 and then in 1996, OBD2 rule, a dedicated EGR vacuum map (baro sensor is used) (engine now has MAF so needs that new sensor)
In 1999 the G16 uses a electric motor driver EGR. (no vacuum malarkey)



the GM cartridge is wrong. 100% wrong GM means Tracker (GEO) and uses the same ECT as the Sidekick here. SE416 cars.. they are... both, (badges different)
keep in mind the +5vref is spec'd at 4.75v to 5.25v so the sensor output varies by that too... it's not a precision sensor at all. given that and it's own resistor spec. and the curve is very non linear above 150F, .
I'ts very inaccurate in the this region. I'd bet the ECU makes no effort to correct errors there. I think it just sees. 150F+ and goes to hot tables....
like thrown a light switch, I'm hot, so the IAC is closed, now.
Keep in mind the ECT does allow to ECU to fuel right at say -30F degrees. when fuel flat hates to vaporize... (and EFI excels here.... really) on the low end.

how ever the hotter engine is more efficient. (well, unless it pings)
and the Radiator too. (Carnots' laws).

the scan tools have there own documents for updates with the maker, and are not covered fully on TSB.s
Most dealers lost these papers long ago. on those old scan tools....

all great questions, thanks for sharing !!!!

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one more fact,
I have the ufiche, the micro films on the GM parts book, "Geo line"
and if you look up the ECU, on those films.
guess what?
next to the GM partnumber is the Suzuki Part-number verbatim , just for ECU's only..
that is why im sure of the p/n match up , these ufilms.
Here are are some other unique things about CAMI cars, (not from Japan actual)
Many USA or Canada parts.
like:
Paint, mine was Corvette red.
Canada Radiator "Harrison"
USA glass.
USA tires and fan belts.
rear shocks? Monroe?
CAMI HVAC....
and more im sure, but never noticed.