2007 LC - Replace ECM (1 Viewer)

[dallasag]

I am getting Code PO335 about once a month - 6 weeks. Mechanic replaced the crankshaft sensor and checked the wiring. Problem still persists. FSM says it could be a bad ECM and to replace the ECM.

Does anyone have any experience with this or the aftermarket companies that provide refurb'd units? An example would be this repair and return option for $180

Toyota Land Cruiser ECM / ECU Repair & Return - SIA Electronics

Toyota ECM repair service. Call SIA Electronics today 800-737-0915

siaelec.com

Many thanks!

 

[wvprankster]

I'm considering a repair and return option as well, but thinking about these folks because they offer a refund if the ECM tests functional:

G7 Computers

Ship your vehicle computer here to be repaired and returned to you, fast.

www.g7computers.com

 

[nukegoat]

I just really doubt that. I have found that the "replace the computer" approach is sort of the random last ditch thing that mechanics default to when they don't want to deal with the problem any more.

 

[99Cruiser]

Did you get the timing belt replaced just prior to getting the code?

 

[suprarx7nut]

I just really doubt that. I have found that the "replace the computer" approach is sort of the random last ditch thing that mechanics default to when they don't want to deal with the problem any more.

Absolutely. That's the line the engineers put in the very end of the manual after they've run out of ideas to cover the extremely unlikely event something gets fried.

I very much doubt the ecm is broken. That's an extremely rare failure, especially in Toyotas.

 

[nissanh]

It could be a worn key at the cam sprocket. I've seen 4runners with the same issue, they replace cam sensor and same problem. Later found out it is a worn cam sprocket or the key. From experience Toyota cam, ABS and crank sensors are for life.

 

[dallasag]

I think mine ended up being a loose connector or bent/shorting wire. After I dropped the dash and removed the ecm, I moved the wires around some and reinstalled it. Hasn’t thrown the code again in 6 months

 

[Travis Bickle]

Absolutely. That's the line the engineers put in the very end of the manual after they've run out of ideas to cover the extremely unlikely event something gets fried.

I very much doubt the ecm is broken. That's an extremely rare failure, especially in Toyotas.

werd... of 12 years working on Toyota's I think I've replaced two ever. Both times they had good signal inputs but nothing on the output side.

 

[wvprankster]

ECM problems seem to be rare. One of the attractions of the repair and return vendor I linked to above is that they will give you a full refund if the ECM passes all their tests. I'll only be out shipping.

I've got code P2118. Checked the ETCS fuse and it is intact. Checked the wiring. Looked good. Throttle body readings were off so we replaced it, thinking the motor or TPS was fried. Still getting code after replacing the TB with new OEM. We are wondering if the ECM is the culprit.

 

[dallasag]

So a year later the Code PO335 is back.

If you see my prior posts, we replaced the crank sensor, checked wiring, and code kept coming back. I pulled the dash and kinda let the ecm dangle for a few weeks in preparation to send the ecm for a repair, and the code went away. Restuffed the ecm back up into the dash and put the dash back together a year ago, and the code never came back for a year.

This is probably a long shot, since I have searched and can’t find any other posts discussing a similar situation, but might anyone have any ideas on what to do? My only thought is that there might be a loose connection in the plugs that go into the ecm and my mechanic is not going to like checking that out. He’s great at mechanics but electrical gremlins really frustrate him. Thanks in advance.

 

[jerryb]

you didn't think about post #6?

 

[abuck99]

If you handled wires and connector leading into ECM and the problem resolved for a year, that's where I’d start looking. Sounds like intermittent open short. But FSM points to 4 possible causes that you check in sequence starting with continuity between connectors. Did your tech try that? This is something you can tackle with out too much trouble.

Here's the Diagnostic procedure for P0335

 

[J1000]

So a year later the Code PO335 is back.

If you see my prior posts, we replaced the crank sensor, checked wiring, and code kept coming back. I pulled the dash and kinda let the ecm dangle for a few weeks in preparation to send the ecm for a repair, and the code went away. Restuffed the ecm back up into the dash and put the dash back together a year ago, and the code never came back for a year.

This is probably a long shot, since I have searched and can’t find any other posts discussing a similar situation, but might anyone have any ideas on what to do? My only thought is that there might be a loose connection in the plugs that go into the ecm and my mechanic is not going to like checking that out. He’s great at mechanics but electrical gremlins really frustrate him. Thanks in advance.

Two things; firstly just check for corrosion on the pins to the ECU. Perhaps some water or condensation got in there.

Secondly, you can try rewiring just the crankshaft sensor back to the ECU using shielded cable like USB cable as it's possible the original wiring has shifted or a new source of EMI has appeared causing interference on the signal line. That happened on my '96 Miata and I replaced just the one sensor's wiring with USB cable and all is well again.

 

[Malleus]

There is a test/validation procedure for every ECU/ECM. I wouldn't replace one, hoping it was bad, before I thoroughly tested it and proved to myself it was bad.

 

[Malleus]

One further note about FSMs: they are FACTORY service manuals, intended for use by dealership mechanics who are "allowed" to work on your truck on a timetable. Some procedures (like intenisve electronic or electrical tracing) just aren't cost effective for the dealerships and will not be included in a published FSM. The Tier 1 OEMs (the companies that Toyta and others buy their parts from) do have test procedures however, because they aren't paid on a time basis. Their profit depends on delivering the right part. It's up to them to figure out how to do that.