R32 power steering Light/heavy

[Rb25orange]

Firstly is it even the diagram I should be referring to ? 
My model year is 1990 gtst 

If yes, pin 8 in this diagram is the final variable voltage as per speed going to the solenoid? And also it goes to the consult port for the what ?

I mean that’s what it looks like, but I am not to sure if it could be going to elsewhere?

Also pin 5 says to ecu I have color matched that wire (brown with silver trace dots) it is wire to one of the connectors that engine/ecu harness connects to but the ecu side of that wire has been chopped so don’t know where that should be on the ecu or can I connect this directly to speedo wire going to pin53 on ecu ? It makes sense to me unless ecu is pulsing that signal or is that signal from speedo already pulsed ?

my only hopes are with you @GTSBoy🙃

also is there any proper wiring diagram on here that could help me 

[GTSBoy]

The ECU doesn't create the speed signal. It is created at the speedo head. That signal is available to all the CUs on the bus that want it (ECU, TCU, ABS, TCS, HICAS, ATESSA).

On that diagram, I can only assume that the "High speed sensor" is the speed sensor/transmitter in the speedo head, and you can see that that wire reports to both the ECU and the HICAS CU on terminal 6 (I think it's 6 - on the RHS up near the top).

The other wire "to ECU" on T5 must be for some signal from the HICAS to the ECU for some other reason. It might be something to do with PS load idle up, or god knows what else.

[TXSquirrel]

I am starting to think it could be your speedo.  I had the exact symptom as described in the flow chart I posted when my speedo cable broke, and my HICAS was untouched.  Is there another GTST local to you that you can perhaps borrow the cluster to test?  It's a fairly quick swap.  

[Rb25orange]

On 15/01/2022 at 11:58 AM, TXSquirrel said:

I am starting to think it could be your speedo.  I had the exact symptom as described in the flow chart I posted when my speedo cable broke, and my HICAS was untouched.  Is there another GTST local to you that you can perhaps borrow the cluster to test?  It's a fairly quick swap.  

It could be, I am yet to check if I am getting a pulsed signal at wire going to pin 53, as in past I took my speedo out, the small device(speed sensor)that creates this signal behind the speedo was all intact and fairly in good condition including wiring and the I did a continuity test from there to wire going to pin53, will update once I have confirmed that. I have been assuming my speed sensor is good I could be wrong though.
 

And I now think hicas could be getting the speed signal independently from the speedo. 

[Rb25orange]

Just Updating for future reference,

Tracing back speed signal wire, it is separate signal to the hicas, so from cluster wire splits into two one going to ecu another to straight to hicas.

Wire is Y/G color on all units. 

[Roy]

I have a new r33 reservoir 8n ky R32 which means i no longer have the reservoir with oil level switch. Im guessing thats why my steering is now heavy?

 

Sigh, now to trace all the damaged loom back to find the wires for reservoir cap with level switch

[GTSBoy]

11 hours ago, Roy said:

Sigh, now to trace all the damaged loom back to find the wires for reservoir cap with level switch

Just look on the wiring diagram, find the right wiring at the HICAS CU and bridge it there?

[Roy]

Yeh. I have looked at the wiring diagram but doesnt appear as though it is the absence of the level switch that is causing the problem. I am waiting for a mate to pull the plug on the cap and go for a drive. I suspect there is something else astray which is why I reckon I just need to go through all the wiring and see from there. The two obvious ones are the speed input and the actual PS solenoid. Maybe with the engine going in and out and all the fluffing around with oil cooler lines/Accusump etc its been pinched. I don't know. For now I am just channelling my inner 18yr old ex Valiant owner 

 

[Duncan]

Most often speed input....is your speedo working....those cables like to break after all this time.

[BK]

3 minutes ago, Duncan said:

Most often speed input....is your speedo working....those cables like to break after all this time.

Yep, stupid things snap right at the back of the speedo where it changes to plastic. I'm surprised no one has made a fully metallic replacement cable by now.

[Roy]

Speedo is mint. Did a cable back in 2001 at Wakefield so know that headache.  It could potentially be that r33 ps pumps have lower pressure??.

[GTSBoy]

On 11/1/2022 at 1:33 PM, Roy said:

It could potentially be that r33 ps pumps have lower pressure??.

No.

I will recount my old story where the power wire for my O2 sensor shorted inside the loom and burnt the wiring for the PS solenoid - giving me 100% dead heavy steering. Loom faults are defo a thing!