Flashing "O/D Off" light

[jspence2]

I have a 2001 Protege ES, 2.0L, automatic, 99k miles. The "O/D Off" light is now flashing at every cold startup. Sometimes if you drive a little ways to get the car warmed up, turn the car off for a few minutes, and then start it back up - the light stops flashing. It does not throw any CEL's.

The car still runs and drives but the shifts feel rougher than normal. Another area of concern is when you bring it out of P and put it in D or R, it clunks. The car never did this before.

Yesterday I drove the car over to a local transmission shop to see if the car was throwing any codes. They had the red snap-on scanner. Of course the OD light did not flash since I turned the car off and on again. They did not find any codes in the engine or transmission side. Nothing pending either. I'm thinking about leaving the car there overnight and have them scan for codes in the morning when the car is cold.

I found some posts from martinmzfan (http://www.mazdas247.com/forum/member.php?u=23663), and I think I might be experiencing the same problem he had with his 01 protege. Here are the threads, 1 (http://www.mazda3club.com/showthread.php?t=41742) and 2 (http://www.mazdas247.com/forum/showthread.php?t=123629221). I'm hoping he will see this thread and chime in. He fixed his car by replacing the EPC solenoid.

Per his thread, I checked the resistance of the ATX case wiring harness (9-pin) terminals (D & I) and it is dead open. It appears that I have the same problem he did, but I'm not sure. I didn't check any other sensors, but I probably should.

I'm tempted to just go ahead and order the EPC solenoid and transmission filter and give it a shot. He listed part number "21-1L1A". According to OnlineMazdaParts.com (http://www.onlinemazdaparts.com/), "Part number FN01211L1A was superseded by part number FN21211L1".

If martinmzfan or anyone else has any suggestions I'm all ears.

[martinmzfan]

Hello. Yeah... I'm still here by checking IM from this board. Rest assured! Jspence2... This definitely and surely sounds like the ATX EPC solenoid is caputsee! It is a common failure on our transmissions. But the good news is it's really, really easy to service this part. If the resistance on those two terminals located directly on the ATX case is reading open, the solenoid is probably dead. You should get a reading between 2.4 - 7.3 ohms. However, though unlikely, it may be a bad connection inside/outside the ATX case at wiring harnesses or terminals or the PCM itself.

I strongly recommend that you wait for the problem to reoccur again and "O/D off" light to flash. Once it flashes in sequence, turn off the engine and restart. If it flashes again, have the TCM/PCM scanned again with the Snap-On Red Box (Mazda data card). A DTC will set in memory after 2 or more poor drive cycles. A malfunctioning EPC solenoid will cause erratic, rough shifting and possibly "clunking" due to the uncontrolled pressures in the ATX shift valves/body. Car is drivable but only to "limp" home or to the garage.

My code was P0745. I ordered the EPC solenoid and ATX filter (PM) from OnlineMazdaParts. That guy is really cool and fast! After you get the part, you need to drop the ATX pan. Of course, collect the ATX fluid carefully and measure it. Mazda uses a RTV gasket but you can find an aftermarket, pre-formed cork ATX gasket locally (hard to find this sucker!) Don't use the beeswax one! I used both the RTV and non-cork gasket and both seeped later on.

Once you drop the pan you can clean the magnet and clean or change the filter too. The solenoid is real easy to locate and I have a picture here somewhere. One 10mm bolt secures the part. Check resistance again on the part harness. Still dead? Change out that sucker. Lube the new solenoid rubber seals with new ATX fluid and install in valve body carefully. Don't overtighten. Reinstall wire harness too. Reinstall filter correctly. Reinstall pan with new gasket! Replace fluid with new stuff and pour in exactly how much you originally drained (Trust me... saves time).

Check back...... for more instructions.... remember, there are other electronic solenoids too on this ATX that may be faulty too. The E-Shift solenoid is another pesky part that fails too. So it's important to get the right DTC stored to narrow down the culprit. Don't just automatically replace parts. All cars fail differently. But... I'm 95+ positive yours is the EPC.

[jspence2]

Martinmzfan! Just the man I wanted to hear from.

My plan of action now is to leave the car overnight at the trans shop and have them scan for codes(with the red snap-on) in the morning. The light flashes upon cold startup every time. Hopefully I can narrow down the culprit from there.

I believe this (http://www.mazdas247.com/forum/attachment.php?attachmentid=74224) is the pic you were referring to, yes I've done some research. :cool:

I will definitely check back here after I get the code. Thanks for the help, I really appreciate it.

[Metallic36]

Hmm.. my automatic Ford Ranger does this, and it's from the shift sensor, but if I push in the O/D Off button to not allow it to have O/D, it does fine. No idea what it would be in a Mazda, but hey, they're related kinda. If I'm driving it without pushing the button in, it will go normal for a while until I gas it and then the O/D Off light starts to flash. If I allow it to flash, it jerks when it shifts into gears. VERY ANNOYING!! You can stop, turn off the truck, then turn it back on and the light will go off, then I can push in the O/D Off button to have a normal truck again.




Martinmzfan! Just the man I wanted to hear from.

My plan of action now is to leave the car overnight at the trans shop and have them scan for codes(with the red snap-on) in the morning. The light flashes upon cold startup every time. Hopefully I can narrow down the culprit from there.

I believe this (http://www.mazdas247.com/forum/attachment.php?attachmentid=74224) is the pic you were referring to, yes I've done some research. :cool:

I will definitely check back here after I get the code. Thanks for the help, I really appreciate it.

[jspence2]

Just got back from Aamco, they used the red snap-on scanner on the car and it came back with 'PO745 - Pressure Control Solenoid A'. I made sure the light was on this time. Looks like our suspicions were correct; time to order some parts.

[jspence2]

Trans is fixed!!!! I ordered a filter/strainer and EPC solenoid from onlinemazdaparts.com( (http://www.onlinemazdaparts.com)highly recommended). The whole process was pretty easy: drain the fluid, drop the pan, clean off old gasket material, install new filter(don't forget the o-ring & lube with ATX fluid), install new EPC solenoid(lubed), throw some RTV on the pan and reinstall the pan. I measured how much fluid I drained out and put the same amount back in. I was in between 3 and 4 quarts.

The car shifts gears silky smooth now, with no more "clunking" when you put it into gear. There is notable difference in drivetrain noise as well; car is much quieter. The best part: no more flashing O/D light!!

Martinmzfan, I can't thank you enough. I saved a ton of money doing this myself.

(cabpatch)

[martinmzfan]

No problem. You're very, very welcome! That was a relatively fun repair job on that car. Just watch to make sure the pan doesn't leak or seep fluid and check levels again about a day after the repair. Always check ATX fluid when the transmission is HOT and go through ALL the gears a few times (while safely parked with handbrake engaged) before shutting down the engine to check the level.

I'm so glad to keep another well-built Protege going!!

[booherbg]

Hi guys. I found this thread (and subsequently the other two threads by martinmzfan) after some intense googling. I think I can relate to the problem you guys had and I really hope that I am as fortunate as you guys.

I have a 2001 Mazda Protege (I think ES) that I bought in May with 116k miles on it. About three weeks after I got the car, I experienced my first "O/D Off" flashing light. The symptoms were as you describe:
* It only happens on a cold start
* It flashes after a 3 second hesitation when I go from park to drive (or park to reverse to drive). The engine engages in "crippled" mode.
* When I turn the car off and back on again, the car shifts into gear just fine and acts like nothing ever happened.
* Since this has been happening, even when the O/D Off light doesn't flash there seems to be about a 1 second hesitation before the car shifts into gear. I think I would have remembered this if it was happening from the beginning.
* Otherwise the shifting is almost entirely normal. I don't know if it shifts at a "high" rpm because the car is so new to me. But sometimes I do feel like it waits longer than it should to shift, but I chalked that up to a property of the transmission.

It may be worth mentioning that my check engine light also came on during this time indicating that my catalytic converter is slow to warm up, or something to that nature. I think that isn't related and will deal with that later.

At first I kind of ignored it, not knowing what the deal was. But over the next two months it became more and more frequent. Right now it can happen almost every day, always after a cold start. And it never happens once the car is warmed up. If I drive down the street and run into the bank for 5 minutes and come back, for example, it always shifts right into gear and off we go.

The biggest problem I'm having now is that I can't get a readout from the computer. The memory is cleared and by the time I get to the mechanic the car is warmed up and the O/D lamp won't come on. I had it with the mechanic for 4 days and the darned thing wouldn't act up for him. Not sure what that's about. But as martinmzfan says, apparently it won't commit to memory unless there are two failed drive cycles. I haven't had this happen yet so I'm hoping to catch the error code tomorrow morning (I left it with the mechanic again). I even tried driving in crippled mode but it "fixed" itself at the second traffic light.

So far the mechanics are suggesting I either ride it out, try to catch the error code, or just rebuild the transmission (of course). I am hoping with everything holy that I can pull a code like the ones you guys are talking about and try my hand at fixing it myself. I've never done anything like this before but I do have a friend of mine who is more experienced with these kinds of things. I've always wanted to get my hands dirt, better sooner than later I suppose.

Does all of this sound like what you guys experienced? Any other suggestions for what I can do until I can catch it in the act and get an error code readout? I like the protege so far and would really love it to last. 116k miles by the way, unsure of how it was treated up until I got it.

[jspence2]

booherbg, it does sound like the same problem I had, but only that stored code can confirm that for sure. Testing the resistance on those two terminals on the ATX case will help narrow it down as well. I had problems getting a code pulled from the car too, maybe leave the car overnight and have the mechanic follow martinmsfan's instructions about it. If you can't get the code pulled, I would definitely try replacing that solenoid before rebuilding the transmission. I think the part cost me less than $40, a trans rebuild is much more costly. I would say it's a pretty easy job if you want to try turning some wrenches.

[booherbg]

Thanks! Looks like it is off to the resistance tests for me.

I have left it with a mechanic for 4 days and every day he was unable to reproduce the O/D off problem. Something in the way I drive the car sets up the proper conditions to trigger the error.

Last night I tried again with a transmission shop, left it over night. Couldn't reproduce the error. I got in to drive it off and I triggered it. Maybe it's my breath?

Either way I was finally able to get a readout DURING the flashing light. And... no error codes were dumped. Frustrating!

Could this be related, somehow, to my catalytic converter problem? Or the high RPM idle on a cold start? The mechanic said that he had an o/d off flashing problem, and he replaced the Neutral Safety Switch to fix it. However he also was able to pull a code from the computer.

What pieces can I pull off to check besides the solenoids? This is part mysterious and the nerd in me finds it challenging, part frustrating because I just want a car that works so I can focus on other things.

[jspence2]

Thanks! Looks like it is off to the resistance tests for me.

I have left it with a mechanic for 4 days and every day he was unable to reproduce the O/D off problem. Something in the way I drive the car sets up the proper conditions to trigger the error.

Last night I tried again with a transmission shop, left it over night. Couldn't reproduce the error. I got in to drive it off and I triggered it. Maybe it's my breath?

Either way I was finally able to get a readout DURING the flashing light. And... no error codes were dumped. Frustrating!

Could this be related, somehow, to my catalytic converter problem? Or the high RPM idle on a cold start? The mechanic said that he had an o/d off flashing problem, and he replaced the Neutral Safety Switch to fix it. However he also was able to pull a code from the computer.

What pieces can I pull off to check besides the solenoids? This is part mysterious and the nerd in me finds it challenging, part frustrating because I just want a car that works so I can focus on other things.

It may be that the scanner he used is not able to pull transmission ecu codes, not all scanners can do that (I think). I don't think the catalytic converter has anything to do with the transmission problems. As far as the neutral safety switch, that was probably a completely different car? This transmission solenoid issue is a common problem for your particular vehicle, which is why I'm willing to bet that is the problem.

The resistance tests on the wiring for the ATX case, and pulling a code, are really the only way to narrow down the solenoid problem - if that's what's causing the problem on your car. Plus, you have to remove the transmission pan under the car to get to the solenoid. If you get anything outside of 2.4 - 7.3 ohms on the resistance test, I would take my chances and replace the ATX EPC solenoid. Cheap part, and it only took me about 30 minutes to swap it out working cautiously.

I don't recall our protege having a high idle during that problem, but that could have an effect on your automatic transmission issues. First step with that would be to thoroughly clean the throttle body, check for gasket/vaccum line leaks, and follow shop manual instructions for setting the idle. However, I still think that EPC solenoid is your main problem.

[booherbg]

Thanks jspence. Both mechanics I tried couldn't pull a code so I'm not sure what the deal is. I'm really hoping it is the EPC solenoid, if for no other reason than you guys have documented it so well. When I get some time I hope to get to the bottom of it.

Thanks again!

[booherbg]

Thanks jspence. Both mechanics I tried couldn't pull a code so I'm not sure what the deal is. I'm really hoping it is the EPC solenoid, if for no other reason than you guys have documented it so well. When I get some time I hope to get to the bottom of it.

Thanks again!

Hi guys! I have a new update, unfortunately nothing good.

OK so I've been working with this problem for about a month now. Here are the symptoms:
* When I cold start the car, and go from P to D, after a 2 second hesitation, the engine shifts into limped mode and the O/D OFF light flashes. This has about a 5/8 chance of happening on any given cold start.
* Once I turn the car off, and back on, the car will shift into D just fine. I have never had a second O/D OFF flashing light situation.
* There is never an "engine code" that can be downloaded, even while the O/D OFF light is flashing :(
* If I switch from P -> 1, instead of P -> D, the engine switches into gear just fine with no error codes. I then go up to D and drive to work, the engine is just fine and gives me no problems.

OK. So that's the current status. No mechanic can help me without tearing apart the transmission. When I found this thread, I decided that it would be in good taste to check the resistance values of the pressure control solenoid and the shift solenoids ABCDE, hopefully finding one that was out of range. I was finally able to get up to my friends house to do this, and we haven't found anything new yet.

My car is currently still in the garage with the 9-pin solenoid cable unplugged.

Results:
Pressure Control Solenoid (D-I) AND the shift solenoids are all within range. :( I was hoping to find one that wasn't in range.

HOWEVER, I did drive my car up here and we worked on it once it cooled off. If I would have drove the car, instead of working on it, I would not have seen the O/D OFF light because it wouldn't have been a cold start. We're hoping to re-check the resistance values in the morning under the assumption that if the engine computer would throw the O/D off light on the cold start, we may see the resistance values in one of the solenoids be out of threshold. SOMETHING is tripping the computer on cold starts... hopefully we'll see something in the morning.

Anyways, at this point I'm completely lost. I don't know what the next step would be. We could do a voltage check to see if the solenoids all "click" with 12V. I'm sure they will because, after all, I can still drive the car once the O/D OFF isn't flashing, implying that the solenoids are all working properly.

Suggestions? It's an extremely annoying problem that doesn't affect me other than making me feel that one day it'll get worse.

[jspence2]

Your symptoms are a little different that what our car was doing. If you want to narrow it down for sure, take the car to a mazda dealership service center. However, it would still be cheaper to just replace the EPC solenoid than paying dealer tech hour fees. If you buy the part from the link I posted above and take it to any auto shop, tell them it's easily accessible with the pan off, it should not be very much $$ to have them replace it. But, like I said, I can't guarantee that is the problem with your car since you can't get any codes and the resistance readings tell you nothing.

No one should have to tear apart the transmission to figure out the problem assuming it's an electrical problem(which I suspect). If it was an internal trans issue, then yes it would have to be torn apart.

[booherbg]

Thanks jspence2. I'm not sure what the next step will be. I suppose heading to a dealer and asking them to check it out might be a good idea.

I'm getting a hold of the Protege technical manual to see what other kinds of computer faults can trigger the O/D Off light. I figure that there should at least be a computer pin-out or diagram. If not the solenoids, then perhaps something else that I can get to and check easily.

[booherbg]

So strangely enough, and i risk jynxing it by saying this, but so far I've started my car 3 times since checking it out on Saturday. All three times were "highly likely" candidates for the flashing o/d off light based on past results.... so far i haven't had any issues.

I'm really, really hoping that by taking out the 9-pin cable and cleaning it, and putting it back in, perhaps i may have fixed something. I am sure that I'll see the light again, but for now, at least it is happening less frequently.