Transmission is slipping

Tiny
BEN LEE
  • MEMBER
  • 2001 HONDA ACCORD
  • 12,600 MILES
This is a 4 cyl, automatic

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.

I should also note that the transmission fluid was changed about 18 months ago.

Thanks!
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Friday, September 23rd, 2011 AT 9:20 PM

22 Replies

Tiny
DRCRANKNWRENCH
  • EXPERT
The fluid and filter should be changed every 30,000 miles. However, in this case it may be worth it to see what happens.
But, before you do that get is scanned for trouble codes.
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Friday, September 23rd, 2011 AT 9:24 PM
Tiny
BEN LEE
  • MEMBER
Thanks, I'll pull the codes and report back
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Friday, September 23rd, 2011 AT 10:26 PM
Tiny
DRCRANKNWRENCH
  • EXPERT
IGNORE THIS MESSAGE. Clear Pending Status. IGNORE THIS MESSAGE
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Saturday, September 24th, 2011 AT 2:20 AM
Tiny
BEN LEE
  • MEMBER
By the way, I typed in the miles wrong before. It is 126,000 miles (not 12.6k)
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Saturday, September 24th, 2011 AT 4:09 AM
Tiny
DRCRANKNWRENCH
  • EXPERT
There are 2 components that you can test manually with a multi-meter.
The first is the Clutch Pressure Control Solenoid Valve, "A" and "B". It is located on the 2.3L, it is located on the right side of the transaxle right by to tab used to hook an engine hoist to remove the engine/tranny assembly. On the 3.0L, it is on the top rear or transaxle. The A and B solenoids are on top of each other. They have 2 pin connectors with "A" having a red wire in connection, "1" and a white wire in connection, "2". The B connector has an orange wire in the, "1" connection and green in the, "2" connection.

To test solenoid;
1. Disconnect harness
2. Measure resistance before terminals. It should be 5 Ohms, if it is not solenoid needs replacement.
3. To check solenoid movement, apply 12V to terminal, "1" and ground, "2". Clicking noise indicates solenoid works.
4. Remove solenoid to check fluid passage for debris/clogging. If debris is removed, repeat step 3. To ensure solenoid still moves properly.

The second component is the Lock-up solenoids. They are located on the right front of engine compartment of 2.3L and the Top front of the 3.0L The wires are either Blue/yellow or yellow from the connector in either terminal.

1. Disconnect harness and measure resistance between terminal, "1' and ground. It should be 12-25 Ohms. Replace solenoid is of of specified range.
2. Ensure solenoid movement by grounding body of solenoid to ground and 12V to terminal, "1" and then terminal, "2". Both should make a clicking noise if solenoid is operating.

Check these solenoids and scan trouble codes then let me know results.
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Saturday, September 24th, 2011 AT 8:22 PM
Tiny
BEN LEE
  • MEMBER
Thank you for these great instructions! Just a few questions before I test. Can you confirm what you mean by "measure resistance BEFORE terminals"?
I don't have a power probe, and I have never applied power to a component for testing before. How do I go about doing this?

Thank you!
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Sunday, September 25th, 2011 AT 9:21 AM
Tiny
DRCRANKNWRENCH
  • EXPERT
First, buy a multi meter as you can get a cheap one for $10 and a good one for $40. It is worth the $40 as it will have test funstions the cheaper one won't.
To test before the terminal means to test the connector end wires. Meaning, don't test the terminal connections on the part you are testing. This test is to see if th epart is getting power, so you want to see if the connector is getting power. If it is not, the problem is before the connector.
To apply 12V to part to test, use the car battery as the powersupply. I usually use it as the ground as well. Get something that will hold the wires to the battery or loosn the post connectors and slip wires in between the battery poast and wire. Before you do this you have to strip the insulation off of the wire to expose the copper strands. Get a wire that is about the same size or larger than the wires coming from the connector and cut them long enough to reach the part tro be tested easilty. Strip some insulation off the other end of the wires and twist them around so they make a point contact and aren't frayed out all over and may touch a contact or ground that you don't want it to. Touch the 12V or, "Hot" wires to the positive connector side of the part you are testing. You can keep track of this by looking at test instructions and use the, "terminal 1 or terminal 2" designations to know which one is positive and which one is negative. The wire color tells you whcih terminal is which and the connector may have, "1" and "2" on it.
It is not hard but be very carful as you can end up touching test leads to meatl and get a good shock and then have to replace your main fusible link. It is really best tro dis-connect to battery from the positive and neagative cable and get large aligator clips or clamps, you can find them at Radio Shack or auto parts store, as it is best to prevent that kind of stuff from happening and if you have anyuthing powered straight from battery it could damge it. Also get smaller alligator clips for terminals in part, these are not as necassary as you are not working in a cramped place and terminals are close together, or the twisted ends will work just fine. You just want to make sure you don't accidnetly ytouch any metal or touch them to each other.
Go through the steps carefully and get prepared as far as getting the right wires, slips and test meters go. Take your time doing the procedure and double check everything before you actually test it. Kind of like, " measure twice cut once". You will have eliminted 2 of some of the most likley causes for your problem. That is how diagnostics goes by porocess of elimination.
Take care.
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Monday, September 26th, 2011 AT 4:38 AM
Tiny
BEN LEE
  • MEMBER
Thanks so much for the detailed input.
You mentioned the possible damage of a component by running power directly from the battery. Is this where a fused jumper wire would come in, and if so, how do I make one.

I also noticed that my Haynes books says to use a fused jumper wire when running power to test these solenoids, but I have no idea how to make one.

Thanks again!
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Wednesday, September 28th, 2011 AT 2:51 PM
Tiny
DRCRANKNWRENCH
  • EXPERT
It is a good idea to make one. I don't know what amperage fuse to suggest. See if your hayne's manual suggests an amperage. More than likely the amperage will vary with the component tested.

To make a jumper wire with a fuse. Go to a local auto parts store. In the electrical section and look for an in-line fuse. There are 3 types, the large double bladed, the small double bladed and the fuse that looks like a cylindrical glass tube.
Check your fuse box to see what type of fuses your car uses so you can get the same type for your test wire.

To make the wire, get the length of wire you need. Consider the fact that you may use it again to test something farther away from the battery. The gauge of the wire is important too as if you want to test something on a 40 Amp circuit, you will need a 10 gauge wire to be safe. Also consider what you are testing as selecting the size of the fuse. Try to find the fuse that is protecting the circuit that the part you are testing is on.

You might want to mount the fuse near the battery as mounting it near the test end may become cumbersome. The in-line fuse will simply mount in-line with the positive test wire. You can strip some extra insulation off the wires if you want. It is probably best to sauder the ends of the in-line fuse holder to the ends of the test wire where you are splicing it into the wire. Make sure you protect it with either heat shrink wrap or electrical tape.

Let me know if you need anything else.
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Wednesday, September 28th, 2011 AT 6:39 PM
Tiny
BEN LEE
  • MEMBER
Great advice, thank you!
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Wednesday, September 28th, 2011 AT 9:57 PM
Tiny
BEN LEE
  • MEMBER
I picked up both a standard ATO and mini fuse holder and some 20' of household (lamp) wire to make some jumper leads. The reason I bought both size fuse holders is so that I would have the option to use either type of fuse. But is there any harm in have a fuse holder in-line with my ground jumper wire also? I know it is not needed, but by doing that I would be able to have a jumper with either fuse size for the hot side if I need to switch them. If this is a bad idea just let me know
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Thursday, September 29th, 2011 AT 9:03 PM
Tiny
DRCRANKNWRENCH
  • EXPERT
There is no such thing as being to safe.
The only problem that I can see is that a fuse is made to protect a circuit. When you make the battery to solenoid test, you are making a complete circuit. The components in this circuits can only handle so much amperage.
I thought about whether the second fuse would be additive to the first or not. Meaning your hot leas has 30 Amp and negative has 10 Amp. The total may be 40 Amps.
Covertly, the smaller fuse is the weakest link and it will blow even under expected load if it is too small.

I think having the fuse on the hot lead is good enough.
I have tested stuff without using any fuses and depended on the fuses in the car to blow to save circuit.

So, stick with the inline on the hot wire/
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Sunday, October 2nd, 2011 AT 3:08 AM
Tiny
BEN LEE
  • MEMBER
I was able to test the lock up solenoids successfully an they were within the normal ohms range and clicked normally when powered on. The clutch solenoid however was more questionable, but I'm not confident in my testing since this is my first time with this type of diagnosis. Ohms measured about 6.0 (5.8-6.0 on one multimeter and as high as 6.2 on a different multimeter.I wanted to use more than one to make sure). I also could not get the solenoid to click when connecting a hot lead and ground to the terminals, but again, I'm not so confident that I did it correctly, so I may try again.

Oh, and I also forgot to mention that there are no stored or pending codes.
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Sunday, October 2nd, 2011 AT 8:03 AM
Tiny
DRCRANKNWRENCH
  • EXPERT
If you got the other 2 solenoids to to test correctly, I think you should be confident.
You have the technique and guidance and I can tell that uou are very thorough.
You pulled information from here and Hayne's, used 2 multi-meters to account for accuracy and made the test wires properly. Are you an Engineering student, if not you should be.

Check on th eprice of the solenoid. Part of Electro-Mechanical diagnosis is hit or miss. It might be part of the problem. The only way you will know is to buy one.
Check prices at Roackauto. Com and USAutoparts. Com.
Rockauto has closeouts and you have to live without a warranty but you can get name brand stuff for unbelievable prices. They will still take returns if there is an issue.
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Sunday, October 2nd, 2011 AT 7:57 PM
Tiny
BEN LEE
  • MEMBER
Thanks so much for all the advice and encouragement. I'm not an engineering student or anything, but I just really like to learn and to fix things that are within reasonable possibility.

I was also wondering. If the solenoid would not click on when powered manually, wouldn't that mean that it would never work during normal operation? I assume the solenoid is working normally most of the time since the car shifts completely normal the majority of the time. Or maybe I just don't fully understand its operation.

Anyway, thanks again!
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Sunday, October 2nd, 2011 AT 10:52 PM
Tiny
DRCRANKNWRENCH
  • EXPERT
Electrical diagnosis is really hard because parts fail slowly or intermitantly. Sometimes you have to wait for them to fail completely befoere you can diagnose the issue and then the part failure may cause other damage.
It is a process of elimination.
The tests are nearly the same except for resitance values. If you have checked the passage of the solenoid and it does not click every time you apply 12V, it fails the test and is working intermitantly. It does not follow the behaviour of the other solenoids as they reacted to the 12V application every time.
I think it is a problem as you said your transmission shifts properly sometimes, the solenoid works properly sometimes.
It may not be the problem, but it is failing and you can eliminate it from the list of possibilities.
I would replace it as automatic transmissions can get damaged when they do not shift properly.
I think you have good mechanical intuiton which is very thorough, you just need to be confident in your findings.
You are replicating what happens to that solenoid under normal operation. The only difference is that the voltage signal comes from the connector.
Check out prices and wheigh the risk. They always say, "$100 in maintenance saves $1000 in repair". Oh so true.
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Sunday, October 2nd, 2011 AT 11:15 PM
Tiny
BEN LEE
  • MEMBER
Any tricks to disconnecting a stobborn wiring harness connector? There are two that I just cannot get to come apart. I don't know if the plastic tabs are just broken, or just not unsnapping for some reason, but I can't seem to disconnect them.
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Tuesday, October 4th, 2011 AT 4:19 AM
Tiny
DRCRANKNWRENCH
  • EXPERT
A really good set of tools for that is to get a set of dental type cleaning tools. Most auto parts stores have them and are often in their bargain bin.
They work great on getting small seals out too.
Also, get some silicone spray. Anytime you need to get rubberseals or palastic apart or protect it, it is what you want to use.
So, spray the connector with silicone spray.
Some connectors can be deceiving. When some connectors need the locking tabs pushed in to release, others may need to have it pushed out to release. You have to look at the connector and always be gentle. Try both ways if you are not sure. Using the dental tools really helps to probe into the connector and see which way the clip needs to be pushed to unlock the connector.
If you happen to break the connector or strip off the terminals. Hot Rod and high performance shops, or go to summitracing. Com, sell connector ends that are weatherproof. You just get terminals that match, they will have them or Radio Shack is good. Then get a good pair of elctrical plyers to strip wires and crimp terminals on wire. Then you have a new connector that you know how to dis-connect. They are not a lot of money either. I think I have seen some at NAPA.
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Tuesday, October 4th, 2011 AT 4:52 AM
Tiny
BEN LEE
  • MEMBER
Thanks, I actually have a pick set and didn't think of using it for this. It worked great, thanks for the suggestion.

Also, I later remembered that you told me to remove the solenoids to check for debris so I also did that, but didn't find any. While the clutch pressure solenoid was off I tested it again with my fused jumper and it worked correctly so I'm a little torn, but like you said I will find out the cost to weigh out the risk of replacing it even if that turns out to not be the issue.

I also had someone suggest to test the transmission range sensor to make sure it is working properly. Do you know where I can confirm what the correct voltage reading should be in each lever position, and which wires are + and - for backprobing?

My Haynes book says to test it by checking continuity, not voltage, but they instruct to do it by removing the connector, then testing continuity between various pin combinations. But what is the acceptable continuity for each position? And how do I shift to the various gears when the shift lever is locked due to the connector being taken off? (Neutral safety swith engaged since the computer cannot recognize the gear you're in)

Hope that makes sense, but just let me know if I can clarify better.
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Friday, October 14th, 2011 AT 9:47 PM
Tiny
DRCRANKNWRENCH
  • EXPERT
I tried to send you this message once, but it looks like it did not make it, sorry if it is duplicate.

As far as the Transmission Range Sensor, I could only find one reference for which I sent you a location diagram. It seemed to otherwise be/or be part of the *****r position switch.

I sent you a voltage pin test chart. You can test a circuit or circuits in a component several ways to test them. Voltage gives you a value while continuity is either open/closed. So, if something that you test is nearly out of the specification range, it is probably slowly failing or internitantly failing. So, I think it will be an interesting test, let me know what comes of it.
I had to send you some diagrams in 2 part top and bottom pieces as they are too small to be usefule otherwise.
As far as the gear shifter, I sent you the locations of the shift solenoid lock and shifter lockout and the gear shift selector on the transaxle. I think you can take the cover off the shifter switch on the transaxle and slect gear by hand.

I wish I had a better answer about the range snesor, so I am sneding you everything I could find in relation to it.

Enjoy! I hope it gets you a few steps closer to your goal. Sounds like you are doing great and are good at getting as many information sources as possible. That is good as even the best information, except for 2carpros, can be different or mis-leading, etc.
Consider joining an on-line enthuisiast forum as you will find people who have been where you are now and can answer some questions I can't since I have not worked on your particular situation, always had manual tranny Hondas/Acura, and you may find that there are things that are not published anywhere are available through fellow Honda lovers. Honda-Tech. Com is a good one and I am a member. I hardley have time to go anymore, but they also have newparts reviews vendor reviews and used parts sales.
Take Care.
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Saturday, October 15th, 2011 AT 2:21 AM

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