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I just started driving this car and I immediately noticed the transmission slipping issues that the previous owner warned me about. This seems to be mostly in 1st gear, either slipping out of gear and back in, or slipping while going from 1st to 2nd.

I wanted to find out all the possible diagnostic steps I could take (a humble DIY'er) before taking in to a specialist. For instance, on my previous car I had some much more severe shifting issues, which turned out to be a faulty transmission range sensor (aka: neutral safety switch) that I was able to diagnose by testing the voltage in each lever position and while driving. It was a $40 transmission fix, so of course I'm hoping to be as lucky this time...

Since this is a new car to me I don't even know where the TRS is yet, but I would also like to know what other types of diagnosis I could do, based on the type of issue I'm having.

Thanks!  

first...

transmission fluid level check...

with the engine running... i usually try to do this with a cold engine so i don't burn my arm reaching for the short dipstick way down on the front of the transmission..

be sure to have a white paper towel .. if the fluid is burned.. it needs to be changed...  hondas don't have a changeable filter.. they have a strainer..  if the transmission oil is very dirty...  you might want to do like the manual says.. drain and refill with fresh fluid.. drive it around the block .. change the fluid again...   drain and refill...   2 or 3 fresh fills...  not cheep.. but thats how honda describes cleaning the strainer..


second..

plug in an OBD2 scan tool... check for any trouble codes...   with a most of the scan tools.. you can see the if the computer sees the gear shift change position in the live data stream..

if you don't have a scan tool... you might look at the harbor freight 98614 version.. as that displays live data


it is totally possible that the clutches are burned out inside the transmission...

but the checks above are done before getting it rebuilt...    and the pricing is usually over 1,500 and under 2,500 for these... depending on where you go...  

Like wayne sad you need to check the fluid level and scan the computer for codes. Also wipe the dipstick on a white napkin or towel and see what color the fluid is. Also if you can try to describe what is happening with more detail.For example...When i come to a stop it goes into neutral and then it clunks back into gear. Or as it shifts into 2nd the engine races up before it goes into 2nd or if i floor it off the line in drive it slips....things like that.

Your range sensor is probably on the back of the trans at the bottom. On the older ones its on the shifter handle in the console.I'm not sure what year it changed.  

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Thanks for the input. I do have a scan tool, so I'll check for codes.

To describe better what's happening...the engine does not really race up like it did on my other car with transmission problems. It just slows for a split second while the car seems to lose gear, then it will kick/jump back in and jerk a little. It is usually not too harsh since it only does it in the lower gear while I'm not going very fast. Usually it will do this when I'm accelerating from a stopped position. Occationally it will do this when it is shifting from 1st to 2nd.  

That doesn't sound like a minor problem but post the codes if there are any  

this sounds like a honda transmission failure mode...

it may go for a while like this..

does your scan tool view live data stream..

with the engine off.. key on i would like you to observe the throttle position sensor voltage as you slowly open the throttle all the way to wide open.. then close the throttle slowly until its totally closed..   the voltage should NOT drop out..   it should be smooth increasing as you open the throttle.. and decreasing smoothly as you close the throttle..

some scan tools can graph this voltage..

next set the parking brake.. look at the transmission range sensor..   as you move it from park to reverse to neutral ..to overdrive to drive to *** you get the idea.... is the scan tool live data showing the expected signal..  sometimes you can graph this signal also..


if your scan tool has record mode.. you can have a passenger trigger it as you drive so you can review the recorded data stream while stopped..  

Thanks for the great info. My scan tool does view live data, but I'm not sure if it shows the transmission range sensor or not, as it is fairly limited. If not then I'll make do with a multimeter and backprobe it to make sure the voltage does not drop off. How do I find out what the proper voltages are for each position of the gear selector?  

Did you scan for codes yet?  

Scanned for codes and there are no stored or pending. I also could not view the voltage of the transmission range sensor or the throttle position sensor on my software, so I'll check those "manually" w/ a multimeter  

Scanned for codes and there are no stored or pending. I also could not view the voltage of the transmission range sensor or the throttle position sensor on my software, so I'll check those "manually" w/ a multimeter  

throttle postion sensor tests normal, so I've ruled that out

how can I find out which wires to backprobe on the transmission range sensor to test for the correct voltage w/ a multimeter in each lever position, and how can I find out what the proper voltage readings should be for each position?

I might have mentioned this already, but the fluid is still the correct red color and level is good also.

I also tested the clutch pressure solenoids and shift solenoids A and B. The clutch solenoid was a little high on continuity, which was about 6.2 and is supposed to be 5, but it did "click" on when I applied voltage to the pins. I'm not sure whether or not to rule that out yet since the continuity was a little out of normal spec.  

The pressure solinoids don't usually fail electrically but the valve bores wear out and lose pressure.  

Is that something that could possibly cause the issue I described? Is there any way to test for pressure loss?  

hi again.. i had to find a honda service manual.. found an earlier model....


but the shuffle between gears is usually a death nell for the honda transmission..   but digging in and checking the electronics is probably worth it.. compared to the price of the transmission...

i don't get deep into the honda transmissions..  as i do electronics not transmission rebuilds..  

thats probably a BAXA transmission model...  or an MAXA model..

in reading something from mitchell../ eautorepair.net

there is a counter shaft speed sensor on the top of the transaxle.. 400 to 600 ohms of resistance...

there is a main shaft speed sensor on the side of the transaxle..
400 to 600 ohms..

i think i would really want to examine these for operation..

i have found in thinking about them.. that the wiring to them gets brittle and fatigues... causing the transmission to shift weird..  

oh.. on the 2001 versions they have make them connectorized..



here is the other...



neither is cheep....

there is also a second clutch pressure switch ,  a third clutch pressure switch... i don't know where it is or what it does... yet...



continuity test on the shifter switch

Park   1, 3, and 10,
Rev    3 & 9
Neu   1, 3 & 8
D4     2, 3 & 7
D3     2, 3 & 6
2        2, 3 & 5
1        3 & 4