[jk14141]

Hi, I have a 2007 Mazda 3, 2.3 automatic. A couple of weeks ago the check engine light and AT light came on (on startup) and the car went into limp mode (would stay in 4th gear and shift roughly when reversing). I shut down the car and they went away when I restarted it.

Then a week or so ago both lights stayed on and the car continued to remain in limp mode. I took it to the dealership. They cleared the codes, at some point disconnecting the battery, and the car worked fine for a couple of days (or about 100 miles of driving) but then the lights came on and the car reverted to limp mode again.

I took it to the dealership again. They pulled P0884 TCM Input Signal Intermittent and P0841 Fluid Pressure Sensor/Switch A Circuit Range/Performance Concern. They checked transmission fluid and said it was OK. They cleared the codes and P0884 TCM Input Signal Intermittent returned immediately. They checked with Mazda tech assistance and they said it was TCM connection to the wiring harness -- the female TCM connector pins were worn and would not hold. They said transmission itself seemed ok.

Unfortunately they said they can't replace just this component but would require the entire harness to be replaced which would be $1k in parts and another $700 or so in labor. Given the age of the car and a number of other repairs I've had recently I'm not thrilled with putting another $2k into it if I can avoid it.

So:
1) Is there a cheaper fix or work around?
2) The car seems to run OK for a few days after the battery has been unplugged. Is that an ok work-around, and if so, is there any risk of damaging the car if I do this?
3) Can I just run the car in limp mode indefinitely?

Thanks, greatly appreciate any expertise you could provide.

 

[hako]

Personally I'd locate the engine or ECU fuse in the fuse box under the bonnet and simply pull that for 30 seconds or so when next it happens. This is easier than disconnecting battery and far more preferable to spending $2000 for what is not a guaranteed fix. I've seen where people put a switch into the circuit to even save lifting the bonnet!
Is the connector visible or is it inside the transmission - if visible why could you not hotwire it meaning solder the connectors or somehow enlarge the pins in the connector so they make contact.
There is always more than one way to skin a cat and dealerships (stealerships) only know one way and that's by the book.
You could also go to a 2nd hand car dealer, preferably one that sells cheaper cars and ask them who they get to "fix or bodgy up" problems on the cars they have for sale....usually they will have someone who can fix anything and cheaply and know all the tricks of the trade.

Good Luck.

 

[jk14141]

Thanks Hako, appreciate the advice. Is there any harm in doing this?

 

[hako]

Thanks Hako, appreciate the advice. Is there any harm in doing this?

In doing what?.....your initial questions were:
1) Is there a cheaper fix or work around?
2) The car seems to run OK for a few days after the battery has been unplugged. Is that an ok work-around, and if so, is there any risk of damaging the car if I do this?
3) Can I just run the car in limp mode indefinitely?

my thoughts (please note I do not like wasting money)
1...wreckers, 2nd hand car dealer mechanics.
2...this should not damage car.
3...limp home mode generally speaking is designed to get you home, however personally if the route I were driving did not include a lot of stop/starts or hills then I would drive in LHM till I had the cash to fix/replace.

Reading your post again, I note that you went to a dealership - I'm not aware of where you live but in Australia you only take your car to a dealership for warranty repairs OR if you want to stay genuine and true to the manufacturers name (or profit).
If you have a transmission problem you should go to a transmission repair outfit where they they specialise in transmissions.

So that is my suggestion - google "automatic transmission repair" and book your car in for a diagnosis - stay away from dealerships unless you want to pay top dollar.

Good Luck.


So,

 

[jk14141]

Thanks again Hako.