ABS & TCS light issue - again!!!

[jonster]

Hi Folks,

I'm looking after a friends '91 NA1 manual at the moment. My normal drive is a DC5 so it's night to experience rear will drive for a change. I've met some of you recently on the North Devon blast where I tried to keep up in the DC5. The NSX was off the road due to a blowing cat-back at the time.

The moment it finally passed the MOT I got the dreaded ABS & TCS light issue along with the power bog-down when you accelerate past ~3k revs.

I've had a good look at the '91 shop manual from NSXPrime but I couldn't make sense of the clip diag method because the wire colours on the diag port didn't seem to correspond to the manual. Because of this I took the car to Honda for them to diagnose. They reported that it's the front left sensor that's failed. This confuses me because having read on here and NSXPrime I thought the power bog-down issue I have implies a rear sensor. Have Honda (Exeter) got it wrong?

Thoughts / help appreciated.

Jon

[simonprelude]

There's a few ports knocking around under the dash, get the right one and the colours are correct (well on my 97 they are) if the front drivers side then it's 4-1 on the flashes, not sure on the other side.

I can take a look if you are local.

I have just had a front sensor changed (only as the car was in Honda anyway), I certainly did not notice anything different than if I had simply switched the TCS off.

Possibly worth doing a ECU reset if it was whilst doing the MOT, I know what the brake tests can do to the ABS settings.


Hi Folks,

I'm looking after a friends '91 NA1 manual at the moment. My normal drive is a DC5 so it's night to experience rear will drive for a change. I've met some of you recently on the North Devon blast where I tried to keep up in the DC5. The NSX was off the road due to a blowing cat-back at the time.

The moment it finally passed the MOT I got the dreaded ABS & TCS light issue along with the power bog-down when you accelerate past ~3k revs.

I've had a good look at the '91 shop manual from NSXPrime but I couldn't make sense of the clip diag method because the wire colours on the diag port didn't seem to correspond to the manual. Because of this I took the car to Honda for them to diagnose. They reported that it's the front left sensor that's failed. This confuses me because having read on here and NSXPrime I thought the power bog-down issue I have implies a rear sensor. Have Honda (Exeter) got it wrong?

Thoughts / help appreciated.

Jon

[britlude]

on a side note, the car brakes should NOT be tested in the rollers at MOT time, the VOSA computer specifically says a road test is necessary! :)


jonster, you have PM!

[simonprelude]

MOT testers not reading the rules sometimes helps us, sometimes not :(


on a side note, the car brakes should NOT be tested in the rollers at MOT time, the VOSA computer specifically says a road test is necessary! :)

[jonster]

Hi Simon / Jon,

Thanks for the quick replies (and PM).

I've been looking under the glovebox side of the dash for this diag port. Is this the wrong place? A piccy would be fantastic.

Looking at a NSXPrime post is suggests that the bogging down isssue points to the rear sensors being the problem. Is this your understanding or a completely separate issue?

I didn't know about the MOT breaking test needing to be done on the road. If this was done on the rollers do you belive this stuffed my sensor? I'll have a word with them if that's the case.

Cheers guys,

Jon

[simonprelude]

I seem to remember it was this one.
It was about 6 months ago though and I have played with a few service connectors since then on different cars.

[britlude]

doing the test on the rollers won't break the sensor, it's more that the abs will get confused why one wheel is turning, and the others not, so VOSA decided that road test is necessary... probably to do with honda recommendations!

as in simonpreludes pic, look for the loose blue connector (it might be in a holder, mine's got one) under the glove box, it's pretty much level with the front edge of the carpet mat, pull it down it should be behind it! short the 2 wires together with a jump link of wire, turn on the ignition (the check engine light will illuminate) and then count the flashes of whatever system shows a fault... it's the same process for all the lamps on the dash!

[jonster]

Great - thanks. Drivers side or passenger?

Did you have the power bog issue?

[britlude]

passenger side, under the very front edge of the carpet toward the outside of the car (ie front upper left corner!!!!)...... just look for the blue connector, it's the only one!!

I don't have any bog issue, and my front left sensor is in the boot, waiting for the replacement!

[jonster]

Doh! Didn't realise I pulled out the wrong connector from the passenger / glove box side. Could have saved spending £150 for Honda to diagnose the fault.

Thanks for all the help.

[madras]

Had the right rear sensor fail on mine, had to wait 8 weeks for the part from Japan but car was perfectly drivable while the TCS and ABS lights were on, no issues above 3000rpm. Occasionally at slow spped when just setting off it would hesistate slightly while it seemed to work out the sensor wasn't working but that was it. Just had no ABS and no TCS.