Pps troubles post dash change - Further issues!

[woggin]

** SEE NEW POST FOR UPDATED ISSUE **

Hey all,

Recently bought my 2nd jza70, pps was working fine, the dash was severely cracked, so i changed the dash, whilst i was there i replaced all the leds on the cluster with regular bulbs since it lit up poorly (and lightly polished the plastic due to scratches, apart from that, didnt touch the cluster) reassembled everything and now the power steering is set to hercules.

Have done some quick TS using the TRSM/TEWD, theres a good +B, a good ground, and a good solenoid (no continuity to earth on either pin and measuring roughly 8.4ohms, within spec)

which leaves me with 'is the pps ecu getting a signal,' evidently not, i plan on pulling the cluster out tomorrow, i am going to test for continuity from the cluster wire to the pps ecu connector, pink wire, blue cluster connector (pin 7), if that checks out ok, where do i go from there? (if the wire is broke I am happy to run my own wiring, but thats assuming the wire is broke.)

Is the speed sensor in the cluster removable? fixable? (does anyone have a pic of it?????) i know daddio (off supraforums australia) was saying the a80 suffers from dead tracks/poor joints, is this common on the a70 too (iam handy with an iron, would just like to know before ripping into it)

as quoted below, i can bridge red/blue & pink wires on the a80, can i do the same on the a70, using the wire on the other side of the speed sensor? (which i believe is the brown wire on the same blue connector)

Failing all this Ill probably make an adjustable power supply and feed it X volts until I am happy with the feel, but would like to fix the stock system if possible.

Its the only thing thats stopped functioning post dash changed, so I doubt ive left a connector unplugged, but will be checking all those connectors also.

Yes I've searched, theres no real info on the speed sensor itself.

this is a JDM jza70 running a r154 from factory, RHD model being JDM (I am in australia, hello!)

cheers for any insight.

And heres the quote from supraforums australia
Daddio, on 30 Sept 2015 - 06:46 AM, said:
PPS ECU gets a speed signal from the odo (pink wire) Odo pass through is known to occasionally fail on the A80 (solder joints on the odo PCB and dead tracks)

As a test, try bridging the red/blue and pink wires behind the odometer with a temporary Scotchblock connector to see if this fixes your PPS issue...takes maybe 15 mins, and is fully reversible.

 

[woggin]

Got into the car quickly tonight, pulled the cluster, the pins weren't correct, nor was the connector , but the wire colours are.

Anyways, there's continuity at the cluster plug and the pps ecu plug, and the clusters speed sensor works, so leaves me with 2 possibilities.

First, the contact on the cluster plug isn't contacting the clusters harness, (carrying out ts as per the tewd wud confirm if the signal is making it to the pps Ecu, but as I didn't have a 2nd person, I cudnt the test as per the manual)
Or,
The pps ecu is fried, since this happened after I played with the cluster, I am gna go with the latter first off...will keep this thread updated though.

 

[hvyman]

Put the old cluster in and see if it works. Not all the clusters are the same. Mixing certain years will not always work.

 

[woggin]

I changed the dash, not the cluster itself. I'll have some time tomorrow to do some more troubleshooting.

Will update with findings.

 

[woggin]

Problem solved!!

Never going to believe what it was, the contact on the cluster board looked like ass, so i got the tip of my multimeter and just cleaned some of the corrosion and protectant (now a word!) off, wiped it down with a bit of iso alcohol, cleaned the other speed sensor wire the same, plugged it in, confirmed the signal to the pps ecu by spinning the speedo drive with a tiny square drive, happy days, cranked it over, pps working sweet!

 

[woggin]

Howdy all again,

SO been driving the car to work a bit, it is approx 20mile (35km) drive, consisting of mainly 65mph zone (100kph) and then some low speed driving to get off the motorway, to the carpark, pps works fine when cold, fine on the motorway, theres a roundabout after i get off the motorway, as i turn in, the steering is heavy, as you pass 1/4 - 3/8th of steering lock, the steering goes light, theres approx 4 more corners after this, on the next corners, theres less and less lightening of the wheel, and once i get to the carpark entry, ive lost all PS, when i hop in to leave, the car is fine and operates as per normal, I was planning to do a flush of the fluid on my days off, but baby kept me busy.

Has anybody experienced this before?

I havent had the chance to do a smaller drive (wondering maybe its heat soak related) to see if it still happens, but would appreciate any input.

 

[woggin]

So, pulled the pps ecu, started the trsm troubleshooting again, not getting any voltage to the connector now...pulled the wiring diagrams out and will start further investigations tomorrow (had to go to work).

time to trace the +ve wire back to its origin, according the the TRSM its the ECU-IG (15A) fuse. Has to be a break, or a short to earth, or if it goes through any connectors (which the TEWD doesnt say there is) a bad contact.

Getting closer and closer to running my own power supply off a switched IGN source and feeding it voltage....but i shall push on!

 

[woggin]

So I am over thinking it, it's a poor connection somewhere on the drivers fuse box junction, it's a big job pulling that out, so prob won't update this for a few days(coz work) but I've found the location of the source of the issue.

Persistance....