speedometer

[Thai GI]

Hi was sent here from the Mercedes forums but here goes with the same post:

Helping my neighbor work on a 88 Honda Prelude (UK Spec E reg) with automatic transmission. It has a speedometer problem the needle don’t register and the S4 light flashes on now and then, he got the car like that. The following is what I’ve done maybe youall got any ideas it should not be that much different to the US models:

1. The speedometer cable housing is a two piece type we took this apart and check the cable (snake) inside.

2. Pull the one from the front going to the dash out it is ok and in one piece.

3. The one going to the transmission is tight on the trans and not coming out, this is suppose to be like this, there is a clip holding it in. I took the clip out and pull the housing out, turn one of the end and it turns, put it back and seat it.

4. We jacked up the car and I turn one of the wheel, cable moves, turn it the other way, the cable move the other way! What gives…

5. Put the assembly back together and took the car for a road test the speedometer still don’t work the S4 light still flashes, I am stomp over this one.

6. Oh about the S4 light, when I looked at the owners manual it said something is wrong with the transmission and to take it in to a Honda service department. I check the fluid and it’s ok color, smell and level.

7. Any ideas is appreciated.

Thai GI sends…

[carotman]

If the cable turns but the needle doesn't move, it might come from the gauge cluster itself

THe Vehicule speed sensor could be bad also.

Does the ECU give any code?

[Thai GI]

1. Thanks for the reply.

2. We took the gauge cluster out for a closer look and found out that the speed part is electronic but the odometer part is mechanical derive from the speed cable (this is all new to me I’m a Mercedes man...).

3. Put everything back together put the cable off the speed sensor end, connect it to a drill, turn the key let the drill rip and hey the speedometer works! So from the cable on back to the gauge cluster is good.

4. Put it back and took it for a test drive but speedometer still don’t work. So it must be the speed sensor, as I’m new to Hondas I wonder why when I jack up the car and turn the wheel and see the cable turn, so why it doesn’t work on the road test?

5. Youall with Honda experience please explain and if it can be repair or we must get a new speed sensor.

Thanks in advance,
Thai GI sends...

[Thai GI]

1. OK we went down to the speed sensor and take a closer look then try to take it out from the trans.

2. Upon doing so it was notice that the two finger thingy holding the unit had broken so the whole assembly was not seated properly. What we did was try to push the unit back down in its proper seat and I hear it engage, also the o-ring might have help with the sealing.

3. Took it for a test drive and it works! Also got no warning lights engine or tranny. I think all this is connected electronically. Then we drove it a long distance for two hours with speeds between 80-110 (this is the UK). Would have gone faster but the tires were not 100%. There were no problems what so ever. This definitely calls for bragging rights…

4. Well I told my neighbor if it works just leave it like this, if the unit happened to pop out then we’ll push it back down like this time. I think they can live with it like this because a new unit is about 130 pounds sterling!


Thai GI sends…

[AZmike]

If you wnt a different one let me know, there was one at my local junk yard last time i check (2 weeks ago). I'm not sure what they'd want for it, but it shouldn't be much. It's pretty small so shipping wouldn't be too bad either.

[smufguy]

if the clip around the speed sensor is broken or wont seat in place. just tie a thin wire aroudn the grap and it should work.