My new pain - 2000 project V70 and random dash lights Topic is solved

[scot850]

Well they are back!!!

After driving a short distance with 3 stops/starts, all was working well with the exception of the turn signals yesterday.

Today, ran a short errand, stopped went into store, and came back out and started the car and immediately the 4 lights of doom came back on. Speedo and trip/milometer went to '-----' again. Tried several times to see if turning the ignition key slightly beyond II would jump the speedo back on. Almost stalled the car, but nothing. Would this tend to point to the ignition switch being ok, or with the fact the issue came on with starting the car point to the ignition switch is a problem? I have a new one and could swap it out if nothing else to discount the issue, but my (large) gut tells me this is not the issue.

The same thing happens, the 3 brake related warning lights come on, shortly followed by the engine check light. After a short while the brake failure light and ABS go off and the engine check and the STC lights stay on.

The trip/milometer came back on the way home, but the 2 lights stayed on. They, when I got near home I stopped at the mail box (on a down hill slope and the orange arrow of doom started flashing.

I switched the engine off, and as I had the code reader on the passenger seat, I checked for codes, and P0600 comms issue was back again! No other trans or engine codes. Switched the code off and for the short (400m) run back to the house, all lights were off again.

I am pulling what little hair I have left out, but does the flashing trans light point possibly to the TCU issue rearing it's head again, or the ABS module or an ABS sensor? I know abscate said you can test the sensors, but where in the engine bay are they connected to? I cannot see where they are in relation to the ABS module.

Really appreciate some direction here guys.

Neil.

[abscate]

Stand by for ABS sensor check photo.....isnt MVS great??

[abscate]

Couldn't find thread, so posted new one.

viewtopic.php?f=1&t=82046

[abscate]

However, if an ABS ring or sensor is damaged the ABS will disable (and the warning light will come on) after driving approximately 100 metres and the light will be reset when you power off the engine, only to come back the next time you drive.

It is actually speed triggered. At about 20 kph/12mph the ABS self-tests, you can hear a 'chirp' or 'burp' when it does this, lasting about 1/3 second. If the self-test fails, the ABS light and/or STC/TRACS will come on, telling you the system is disabled.

If you drove 5 km, it passed the self test, and you have either a bad connection or sensor. It is possible the ABS module is iffy, passes the test, then fails shortly thereafter.

These things fail really safe - don't worry about your safety or losing your brakes or something like that.

[scot850]

Thanks for the link and pictures. I'll have another closer look where the connectors are. Couldn't see them at all last time I had a look.
What were the 'good values' of resistance I am looking for, or am I looking at continuity only?

Matty still gives me the impression he is not convinced it is the ABS module. If it is not, then other than the ABS sensors or possibly the sensor ring being faulty not sure where else to look. I'm not expecting replacing the aBS module wit a re-man'd unit from Matty to fix all the issues, but maybe the majority of the brake related ones and possibly the speedo.

I think what is causing the doubts is the randomness and the fact that the lights often go out after a while. I think it is temperature related and that would be a classic solder/wiring issue.

Neil.

[abscate]

My advice next to Matty on ABS is like my string theory next to Feynman.....

My rear ABS sensor on the 99 has been soldered 4 times and it comes and goes - they are trick buggers once the wire gets knackered.

I didn't get a good reading on my Front ABS sensor when I took that picture,its tough to get the Ohm probes in the right place with only three hands.

Matty reports 900+- 300 Ohms on his website. Make sure you are on the right side of the connectors!! Follow the wire down to the wheel! The bottom connector goes to the ABS controller on my car at least!

[scot850]

Thanks my friend, I will follow the wire to make sure I'm testing the correct end!

I have asked Matty to invoice me for a re-built unit. It may not fix all the weird stuff, but hopefully at worst, it will eliminate the ABS module as an issue. By the time it gets here I hope to have time to test the ABS sensors and check the wiring harness at the ABS pump/module more closely.

I found what I think it the 2 connectors based on your excellent photos (thanks). The RHS front is fairly obvious but the LHS front is hidden under the front fuse box that is why I didn't see it first time around.

Neil.

[scot850]

So found the 2 connectors (the LHS I had to lift the kidney shaped fuse box out the way and the connector is hidden behind the main wiring harness from the main fuse box. Another fine design especially when you have big fat hands!!). RHS came apart easily, and I cleaned both sides with electrical cleaner and blew them out. Checked on 'Continuity' setting and both sides gave a reading of approx. 660. They only read one way around. Testing the pins in reverse gave the -1 reading, so assume they must be 'orientated' to check them. I am not electrical in the least, but assume this is the setting to test the resistance with and not the 'Ohm' setting which gave -1 when used.

I have removed and cleaned the main ABS module assembly and the power connector to the pump. Best I can tell the wiring looks in pretty good shape I'm guessing due to the car being an NA and not having a great big hot turbo under it. I cleaned both sides with electrical cleaner and will let thoroughly dry out/evaporate and then will carefully reconnect the connectors. I'll take Matty's advice and re-seat the connector a couple of times to make sure it seats properly.

Still have to check the rear sensors, but hope they should be ok as I have not disturbed them during my working on the car, but that does not mean one is not bad. So will pull the floor up to check them too.

Is there any other speed related sensor I should be checking? Does the transmission have a speed sensor or does it take the speed reading only from the ABS sensors?

Neil.

[Teddy1975]

Hi Neil.

Regarding the transmission speed sensor, it seems only older V70s have them as per this old post:

The 99+ cars don't have a VSS (Vehicle Speed Sensor) in the traditional sense. The computer network uses the speed as detected by the ABS module to show the speed on the instrument cluster display. If your speedo is doing odd things, there's a good chance there's a fault with the ABS module, it's pretty common on our cars.

One of the ohm settings should really be used when measuring resistance, but it does sound like your meter stated the ohms while set to measure for continuity too.

Maybe it's a viable/quicker solution to have a tested ABS module sent from Matty to see if it makes a difference?

I hope you get it sorted, I think we all know how annoying it can be to find faults on our cars.

/Teddy

[scot850]

Thanks for the input and encouragement Teddy. I have a tested re-built unit on it's way from Matty as we speak. In the interim I have cleaned all the connections at the front end of the car. Both ABS module connections (the main connector pins looked a little oxidized) and the 2 ABS sensor connections have been cleaned and re-connected.

I had to remove the battery -ve as I realized I thought I had cleaned the ground on the LHF strut tower but I actually hadn't. So removed it and the bolt head to wire end connector looked nice and clean, but found once the bolt was removed there was a bunch of oxidization crumbs/powder left in the hole threads. Cleaned them all and reconnected it. Naturally having had the battery disconnected and resetting the engine check-light P0600 comms. error yesterday currently there are no warning lights on. Need to take it for a run again to see if it all comes back again. Even if nothing does come back on, once the ABS unit arrives I will probably swap it out anyway as it is a good chance it is near failure with age anyway.

Thanks for the note on the lack of speed sensor on the transmission. That reduces the issue to more likely being in the ABS system for the majority of the issues.

Neil.