Check Trans and Engine light (code P1870)

[trooperbc]

yes, for the OBDI system (pre1996) you just jumper two connectors with the engine off ignition on and 'read' the flashes counting each flashes as a pair, for example 12 (which is the first one to show you the system is working) is one flash pause flash-flash (which is 1 and 2, which is 12).

only problem is i don't know where the connectors are in your rodeo,...try a search here.

btw, you might have better luck on something like this starting your own thread, to get quicker and better responses...

//bc

[Kaobb]

bc, thanks for the info. Do you think the EGR could be the problem or does a 1993 Isuzu Rodeo have oxygen sensors tha tcould be an issue? The "CEL" doesn't come on right away it takes 10 to 15 miles before it rears it's ugly head. Seems like it has to warnm up pretty good. The temp gauge is good.

Thanks for any help.
k

[atfdmike]

DIAGNOSTIC TROUBLE CODE (DTC) NO. DISPLAY

1. When the DTC test lead in the vicinity of the ecmis connected with the ignition switchturned to ON position, the diagnostic trouble code stored in memory is displayed in the MIL.
2. With the engine not in operation, first, the DTC 12 is indicated three times, which means that the ecm is functioning normally. Then other DTCs indicating other malfunctions, if any, come on three times each in the ascending order of DTC numbers.
3. The malfunction DTCs are also read out when the engine is running. In this case, the DTC 12 is not indicated.

I don't think there is an 1870 code for the engine that far back. Once you ground the DTC the flashing CEL will give you a two digit code. If memory serves, 32 is code for egr problems.

[trooperbc]

and the codes are *stored*, usually. so the light doesn't have to be on for you to read the codes that are stored in memory. after you do the reading, clear the memory by disconnecting your battery for 30 seconds so that you can retest for any new codes set; otherwise you will be reading the same old code.

egr valve can be an issue. and you do have a single 02 sensor which can be an issue. read the codes and go from there. imo.

//bc

[Kaobb]

Atfdmike and bc, both of your post is very good. Unfortunately they are a bit over my head in understanding them. A couple of Q's for both of you if you don't mind.

"When the DTC test lead in the vicinity of the ecmis connected with the ignition switch turned to ON position, the diagnostic trouble code stored in memory is displayed in the MIL."

Mike- What is ecmis and do I connect it with the DTC test lead and if so how do I do that?..... and where is the MIL?

Once you ground the DTC the flashing CEL will give you a two digit code. If memory serves, 32 is code for egr problems.
Mike- What do you mean by ground and how do I do it?..... and where will the code be displayed?

and the codes are *stored*, usually. so the light doesn't have to be on for you to read the codes that are stored in memory.

bc- What light doesn't have to be on?.... where is the light located and do I clear the codes by disconnecting the battery first before a jumper it?

Sorry to be so thick headed. My father was a very good electrician but I did not get any electrical ability from him unfortunately.
Thanks for your help guys,
k

[RodeoJ]

I have a 2001 Rodeo. Last July the Transmission light and check engine light came on together. We were going about 72 mph. Pulled over, turned the truck off then back on. Took off again - discovered that we were okay at about 68 mph - anything over that for a long period of time and the lights would come back on. The transmission would not stay in overdrive. Had to have transmission rebuilt - now it's better than ever. Only have 85000 miles.

[Ramblin Fever]

RodeoJ - did you have your alternator tested for output *before* you replaced your transmission??

I can't even count how many people were told and could swear their trannies were failing, when in fact the alternator wasn't putting out the power to force the shifts. These Isuzu's are voltage happy vehicles and will behave oddly, even sickly, if they're not getting enough juice.

[surferfletch]

Sounds like there is good used 4L-30E out there with only 85K on it...

[RodeoJ]

I did not have my alternator checked first. Could a bad alternator have caused the damage to my transmission? I truly trust the mechanic that fixed it and do not believe I have been taken advantage of. When going 65 the RPMs were over 3000 - now they're just above 2000 at 65-70.

[trooperbc]

Originally Posted by RodeoJ

I did not have my alternator checked first. Could a bad alternator have caused the damage to my transmission?

no. bad alternators on isuzu's create lots of weird symptoms and problems, like with the fuel pump, with dash lights and with weird automatic transmission acting up. but it's not so much that a bad alternator would damage the transmission as that a bad alternator might be mistaken (knowlingly or unknowingly) as a bad transmission. in your case, it's water under the bridge, and you've said the rebuild solved your problem -- so that's that. you will probably hear that the 4L30E automatic transmission doesn't seem to take kindly to rebuilding, but again, that's done, so just take good care of it with fluid and filter changes...and enjoy.

I truly trust the mechanic that fixed it and do not believe I have been taken advantage of.

that's great. care to share?

When going 65 the RPMs were over 3000 - now they're just above 2000 at 65-70.

just curious, what did the mechanic say was the specific problem?

thanks


//bc

[RodeoJ]

The shop I went to is Metro Transmissions in Columbus, Ohio. I believe it is family owned. They also adjusted the bill to stay within their original estimate.

The exact problem was that the overdrive clutch was "gone". We replaced the clutch, torque converter, gaskets, solenoids, etc. eek:

Thanks for your comments!

[Pink Bits]

Have read all your threads with interest. About once a week my 1999 Rodeo Check Trans light starts to flashes when you go to start it up. You have to wait a minute then it starts OK.

It's been to the mechanic twice, last time it had the filter changed, tranny flushed he said all is fine. Problem occurred again so took it to the autotransmission guys - and they couldn't find a problem. Recently had to change the battery, and he checked alternator and said all is fine (which now makes me wonder is it really OK).

Mechanic at Holden said that it might be something to do with the wiring - next time it happens call them and they will see if they can fit us in, which is handy if they can't.

I think it's an electrical problem more than a tranny problem, but where do I start, replace alternator or look into the wiring? Any suggestions would be greatly appreciated.

Thanks & Regards

[2eyefishclaw]

P1870 trans component slipping
usually indicates that the torque convertor is starting to fall apart (internally)
sometimes flushing the trash out of it will help for a while but its only a temporary fix for major trans damage best bet is to flush trans replace torque convertor and flush trans again

[VinceH]

I had the same code come up with the tans light flashing, also the lights on the gear selector would indicate "N" even though we where in "D". After doing many of the checks like pulling the alt. off to check it's output and haveing the battery checked which all came back ok. I also took it to a few shops that said that I would have to change out the tranny. Not wanting to just fork over that kind of money I did a bit more research and found a local guy who was highly recomended by many. What he had found to be the problem was the range position sensor to be at it's maximum available adjustment. Hhe replaced it, changed the trans filter and new oil and now all is well. Better downshifts and response.
Do your research before allowing anyone to tell you that you will need to replace such an expensive part. A tranny should not be needing to be replaced so soon unless you have never taken the time to take care of it.

[VickyLou]

OK, I have a 1995.5 Isuzu Rodeo (same 4L30E transmission--YUK!), and I've recently had the "Check Trans" and "Check Engine" lights both come on, at separate times. I had the error codes read, and though I didn't get error code numbers for the transmission, they said the errors pertained to the TCC and shift solenoids. Does anyone happen to know the codes for those, on the OBD-1 system?
And also, could I correct such a problem just by changing the A/T fluid? Since not being able to drain it out completely doesn't help any, and since I haven't been able to get an accurate reading on the dipstick, I'm switching to Plan B-- install a drain plug in the pan myself.
Anyone have any better ideas?
Thanks!
BTW--the engine error code was 44, which is "System Lean Driveability". Anyone have any suggestions on how I can take care of that before I have to get ready to pass my smog test in December?
Thanks again!