TCS light on but it's NOT the transmission

[gregcoad]

The check engine light came on a while ago followed shortly by the TCS light. But WAIT... It's not the transmission. I checked the code and the only code that is stored is 0904 indicating EGR insufficient flow. I already had the tranny rebuilt in 2010 by Mister Transmission (they use revised after market parts to address the design flaws interest original, giving you a better-than-new transmission when all is said and done). So needless to say I was panicked, at first, but then very relieved once I had read the code.

So the TCS light comes on and stays on fairly frequently lately. Once the van is shut off, the light goes out and doesn't come on again for a few days usually. There are no codes being thrown besides EGR. But the check engine light is on constant due to that so I can't see this intermittent TCS light having anything to do with that. I just replaced front pads, calibers and rotors, thinking that worn brakes (they were in pretty rough shape), may have been leading to brakes overheating, which will shut down the TCS system according to the owners manual. But the light is still coming on fairly frequently. I haven't looked at the rear brakes, but does the TCS system even use the rear brakes or have sensors at the rear wheels?

How else would I go about diagnosing the cause of he TCS light?

[New Dad New Van]

I don't know about that 0904 code as Honda codes are PXXXX format.

Get the code read again for the CEL and TCS. If it is the EGR, then read up on it and perform the cleaning of the ports and the replacement of the EGR valve.

[gregcoad]

Whoops. Don't know where "0904" came from... It was "P0401". But I don't think that has anything to do with the TCS light coming on. I plan on doing the EGR fix but this TCS light seems to indicate some other issue. Otherwise, I would think that the light would stay on constant, until the indicated code is cleared, as the check engine light does. The TCS light is behaving quite differently.

[davedrivesody]

+1 for EGR. The TCS light comes on for a multitude of reasons (unrelated to the TCS or brakes) including EGR problems.

[Yoraweener]

I had the same issue on my 02.The check engine light was on and shortly after driving it the TCS light came on.Mine kept saying missfire on cylinders1,3,5.Replaced with new coils,changed the plugs and still no go.It wasn't until I joined on to this forum that I learned that the EGR ports get plugged up so I took the intake off and OMG!!.This thing was caked full of carbon deposit liked someone packed sand in there.Anyway,cleaned it all up with some brake cleaner and seafoam and put back together.Took the negative cable off the battery to reset the CEL and Bingo,no more warning lights so far.Drove about 150 miles on it and still no warning lights.Also runs better.Hope that helps and thank you Ody forum.

[mmeyer4663]

I just went through the same thing on my '01, currently at 302k miles. Turned out to be the EGR valve. Honda dealer wanted $675 to replace the valve and open up the "throat". I check my records and we had the same problem back in '05 @ 122K miles. Back then we just replaced the EGR valve and it last 180k miles till the last week or two.
At some point, maybe, we'll do the full deal and open up whatever they suggested.
Will be interesting to see how long this one lasts.

[bruce2]

Honda dealer wanted $675 to replace the valve and open up the "throat".

I did'nt realize I have saved $600 by cleaning out my EGR port in less then an hour of work. Honda is really making real money now a day.

[sontakke]

I can confirm that at least on 1999 when EGR code pops up, TCS light will stay on until restarted. It will come back on again when the EGR code transitions from pending to current. I can also confirm that when you erase the codes, the TCS light will stay on until ignition is cycled (very irritating)