Check Trans and Engine light (code P1870)

[matt2000]

Originally Posted by 2eyefishclaw

no harm will come to the PCM you could leave them together fo a year and you will not damage the PCM all your doing is discharging all electronic components it is not a quick fix for anything but a real good way to clear your dtc after you get the tranny flushed and it will also reset the PCM it may run funky for a while because all it goes through a learning process about 1,000 to 1,500 miles

hi,
Im new here I just want to know it is also applicable to my Isuzu trooper 3.1 diesel. I have a problem my speedometer is dead and the check trans is blinking. When I replaced a new speed sensor the speedometer works again I think it was already corrected the problem. I notice to my trooper the check trans start blinking again every 1.8 KM over and over again. I think I have to clear the DTC. Is this is the procedure to clear the DTC in TCM?

Thanks,
Nap

[SilverLS]

I had the same tranny code come up - and it also did not go into backup mode.

I had them flush and fill the transmission fluid. Light came on two more times after that (I reset it both times with no further service) Since then (about 3-4 months ago) the light has not come back on. I suggest trying that before considering a new transmission. I wouldn't change it until you have trouble shifting. If it ain't broke, don't fix it.

[matt2000]

Originally Posted by SilverLS

I had the same tranny code come up - and it also did not go into backup mode.

I had them flush and fill the transmission fluid. Light came on two more times after that (I reset it both times with no further service) Since then (about 3-4 months ago) the light has not come back on. I suggest trying that before considering a new transmission. I wouldn't change it until you have trouble shifting. If it ain't broke, don't fix it.

hi silver,
I already flush and fill the transmission fluid and also remove both + and - of the battery and touched the two cables for 15 seconds but still the check trans is blinking in every 1.8 KM I ran. The model of my transmission is AW 30-40. My trooper is import from japan Isuzu Bighorn 3.1D 1993 lotus edition. The engine is good and I didn't notice any failure in my transmission. Im here in the philippines I will try to look any shops that have a scan tools to delete the DTC code that stored in the TCM memory. Its kind of weird because it only occured everytime I reached 1.8KM in my odometer still blinkin when I shut off the engine and restart again it will blink again in the exact 1.8KM that I ran. Thanks silver I think there is no problem in my transmission maybe it needs only to remove the DTC in the TCM memory.

[Tespin]

My '01 Rodeo LS was having similar problems.

The check engine light and Trans light would come on and would either shut down or go into "limp mode".

My mechanic thought it was the EGR, but after I cleaned it and some money later we found out it was my wiring harness.

They temporarily fixed it by zip tying some of the loose wires secure and since then everyhting is fine.

Im getting a new wiring harness put in next week, but the temp fix has held for now.

Check your wiring harness....

[SilverLS]

"hi silver,
I already flush and fill the transmission fluid and also remove both + and - of the battery and touched the two cables for 15 seconds but still the check trans is blinking in every 1.8 KM I ran. The model of my transmission is AW 30-40. My trooper is import from japan Isuzu Bighorn 3.1D 1993 lotus edition. The engine is good and I didn't notice any failure in my transmission. Im here in the philippines I will try to look any shops that have a scan tools to delete the DTC code that stored in the TCM memory. Its kind of weird because it only occured everytime I reached 1.8KM in my odometer still blinkin when I shut off the engine and restart again it will blink again in the exact 1.8KM that I ran. Thanks silver I think there is no problem in my transmission maybe it needs only to remove the DTC in the TCM memory."

You don't need to go to a shop to clear the codes. I just bought a scan tool from harbor freight for $40. Just plug it in and after it cycles throught the codes 4 times it will aotomatically reset for you. Here is a link for the tool:

http://www.harborfreight.com/cpi/cta...emnumber=46030

[matt2000]

Originally Posted by SilverLS

"hi silver,

You don't need to go to a shop to clear the codes. I just bought a scan tool from harbor freight for $40. Just plug it in and after it cycles throught the codes 4 times it will aotomatically reset for you. Here is a link for the tool:

http://www.harborfreight.com/cpi/cta...emnumber=46030

Hi silver,

thanks for your reply. My trooper is 1993 model the scan tool is only fit for 1996 onward.

Cheers!
nap

[SilverLS]

Oh, my fault. Well, from what I understand, disconnecting the battery for about 15 seconds or so should do the same thing. But I'm not positive. Might want to post a new thread asking that question. I'm sure some one on here knows for sure.

Good luck.

[Kevin Baker]

Originally Posted by pm77

Hello,

I have 1997 Isuzu Rodeo (automatic, 4wd) and Check Engine and Check Trans. light is showing up. Trans. Light is flashing. Not sure what is wrong. Trans. gears seems to be switching fine.

I took it to the mechanic and after inspecting he is getting code P1870 (component slippage). Is this something to worry about. I am planning to keep the truck for a while. Also how much the replacement cost?

Thanks a lot.

I have an 1999 Isuzu Rodeo. Which has the same problem mentioned here. CEL and Tranny light are one, but Tranny seems to work fine (no slipping). Code P1870 was what my mechanic said it was. I had the fluid flushed, but didn't get the filter changed. I was told the fluid was really dirty/old. I had never changed it, and it has 80K miles. The lights still come back on after a while. They didn't change the filter. I was wondering how import. that was?

He told me this code was due to a mismatch in a comparison of the speed at the front end vs. the back end (not his exact words) of the tranny.

[mtndog]

I have the same problem on my 95 Trooper. I read on other forms about a voltage spike causeing the problem. Well I just verified it, I hooked up a multimeter to my Batt and drove around a while and every time the check trans light came on the voltage spiked to almost 18v

[mtndog]

I had read some of the problems with the check trans light and in my case it was the altenator. When the internal regulator statrs going out it was caising a spike to almost 18v and freaking out my computer causing it to go into "limp mode"off and on about 3 times in a 2 block distance. Changed out the altenator problem gone. Now the cause of the altenator going bad was probably because of the great idea of putting the altenator below the power steering pump so any leaks go right into the altenator. Fixed the power steering pump leak got rid of the oil soaked alt all is good.

[kjmcdonald]

This just happenned to me yesterday. The light started flashing on my commute home. Actually on Sunday, at the beginning of 260 mile round trip, I had thought it was shifting wierd (or not engaging the mechanical lockup when I was used to.) The rpm's seemed different than I remember given the speeds the truck was going. The rest of Sunday's ride, and all day monday, even after the light started flashing, the truck seemed better, Shifted where I remembered. RPM's even dropped when the lockup engaged.

I checked the computer codes this morning and it was P1870.

I then had the transmission flushed, and then the filter changed - took much longer than the shop thought it would since they didn't realize they'd have to unbolt one of the cross memebers to get the pan out.

I'm very encouraged to hear some of what's being said here. I think I have reason to suspect an electrical problem too, Hopefully someone can help me figure out what to do from here...

For a while I've been wondering if my alternator was on it's way out. Over a year ago my battery wouldn't hold a charge (original battery) I had it tested and replaced, and had the alternator tested too. It passed, which surprised me since at idle the interior and dash lights, and radio and clock LCD backlights, all flickered noticeably. But it passed.

Lately I haven't been sure, but I've been thinking the flickering is getting worse. It seems to diappear when I hold my foot on the gas and boost the RPM's.

Anyway, given this electrical problem is it worth replacing the Alternator before I go and spend a ton of $$ on the tranny? Even if the Alternator passes it's tests?


Any other advice? How does it compare pricewise to replace a torque converted instead of a whole transmission?

-Kyle

[trooperbc]

Originally Posted by kjmcdonald

...
For a while I've been wondering if my alternator was on it's way out. Over a year ago my battery wouldn't hold a charge (original battery) I had it tested and replaced, and had the alternator tested too. It passed, which surprised me since at idle the interior and dash lights, and radio and clock LCD backlights, all flickered noticeably. ... I've been thinking the flickering is getting worse. It seems to diappear when I hold my foot on the gas and boost the RPM's.

well something is not right with your charging system. top suspect is the alternator. depending where you got it tested, like at a bigboxpartsstore, the test might not be indicative of what's really going on.
but your flickering and steady with increased rpms does indicate a charging system problem. but it just might be the belt not adjusted and/or battery cable connectors and/or grounds, which might be the thing to check out first.

that's where i would start anyway...

//bc

[Cat Fuzz]

Ok, this thread is so old it starting to mold. Usually it would be good to start a new thread with a reference to this one.

[surferfletch]

Over 5K views, though.

[Kaobb]

I have a 1993 Isuzu Rodeo. Check tranny light was falshing about 2 months ago and had a grarage hook up diagnostic machine for $75. He told me it was the alternator amongst other things. I changed the alternator only and that fixed the tranny flashing light problem.

It ran fine.......
NOW I have the "check engine" light on. Advanced auto and Auto Zone's tester starts with model year 1996 and above.
My question is, IS there a way I can find out what is triggering the "check engine" light without going the $75 route again to find out?

I have read in the owners manual that it is something to do with the emission system. Anybody have any expirence with that??
Any help is appreciated.
k