TPS Breakout Harness

[docc]

Casper TPS harness came really quickly. I tucked the yellow wire in and added shielded bullet connectors to easily clip on a DVOM, red for positive (nero/viola or purple/black wire) and black for negative (viola or purple wire). Pictured next to my "backprobing instruments"

 

Looking forward to comparing voltages at the TPS to that seen in the ECU through guzzidiag.

[Camn]

Back in 7/2012 I measured voltmeter V / GuzziDiag V: 0.160V/0.000V [-1.41Deg], 0.470V/0.465V [3.03Deg].

[docc]

Back in 7/2012 I measured voltmeter V / GuzziDiag V: 0.160V/0.000V [-1.41Deg], 0.470V/0.465V [3.03Deg].

That certainly confirms that the TPS cannot be set at baseline through the ECU, but requires voltage measurement at the TPS itself.

 

Thanks, again, Camn!

[docc]

 

Back in 7/2012 I measured voltmeter V / GuzziDiag V: 0.160V/0.000V [-1.41Deg], 0.470V/0.465V [3.03Deg].

That certainly confirms that the TPS cannot be set at baseline through the ECU, but requires voltage measurement at the TPS itself.

 

Thanks, again, Camn!

 

Camn's observation is confirmed. While the voltages at idle are very similar (+/- 0.001 mV), at the 150mV baseline at the TPS through the Casper breakout harness and a DVOM, guzzidiag reads the throttle voltage 0.000.

 

I'm thinking a new "tune-up" thread is forthcoming based upon these new tools and developments.

[Zooter]

 

 

Back in 7/2012 I measured voltmeter V / GuzziDiag V: 0.160V/0.000V [-1.41Deg], 0.470V/0.465V [3.03Deg].

 

That certainly confirms that the TPS cannot be set at baseline through the ECU, but requires voltage measurement at the TPS itself.

 

Thanks, again, Camn!

Camn's observation is confirmed. While the voltages at idle are very similar (+/- 0.001 mV), at the 150mV baseline at the TPS through the Casper breakout harness and a DVOM, guzzidiag reads the throttle voltage 0.000.

 

I'm thinking a new "tune-up" thread is forthcoming based upon these new tools and developments.

did that happen? I am getting set to order the ''tools''.

[docc]

eh - no gumption lately to tackle the updated tune-up tutorial.

 

The TPS harness is a must and the cabling for Guzzidiag makes the tune-up so much easier as well.

[Kiwi_Roy]

I believe the only reason for setting the base line at 150 is so the TPS is not jambed against the stop at either end of travel.

 

 

I had a fuel mixture meter on my bike for a while and found I could vary the mV +/- 100 mV with very little effect on the mixture ratio.

The funny looking clock is a pot that allowed me to offset the TPS mV on the fly adding or subtracting 200 mV from baseline.

The mixture meter's showing 22.4 because the engine's not running, I think normal is about 14 from memory.

I mounted the O2 sensor in the crossover.

[Zooter]

I have a pair of mystery aftermarket looking bullet push connectors similar to Docc's pic which disappear into factory looking harness below Magnetti Marelli ECU bundled with the ECU spaghetti and OBD outlet. Wtf? At idle there is 1.5V between them rising to 1.6v with a throttle blip. Isn't that 10x 150mV ? Yes I am on single figure whole V range.

[Kiwi_Roy]

What colour are the wires?

You won't normally see 150 mV on the TPS, it would be about 400 mV once the idle speed is set.

I don't think the 2 wires are TPS but who knows what a PO may have done, I just identified the wire on mine and put a connector adjacent to the plug. A blue butt connector makes a cheap meter jack.

 

 

Sent from my shoe phone!

[Zooter]

Black. Very tidy mystery.

[Kiwi_Roy]

If you were to unplug the ECU and unplug the TPS you could easily check with an Ohmmeter if the mysterious wires

are connected to the TPS.

If you are indeed getting 1.5 Volts at the slider you need to reset it for sure.

 

 

There's quite a bit of confusion as to how the TPS is wired, if I look at the various schematics for bikes with

the 15M ECU almost half show the slider as pin C of the TPS going to pin 11 of the ECU, the other half

show the slider as pin B of the TPS  again going to pin 11 of ECU but the odd one shows the slider going

to ECU pin 1

TPS pin A seems to be chassis in all cases

From pin A to the slider will vary in Ohms with throttle position

From pin A to the other end of the potentiometer will not vary with throttle position

The TPS has extra circuitry inside, it's not just a simple Rheostat as the schematics show. the resistance

doesn't vary in a linear fashion as the schematics would have you believe.

 

I think pin 1 of the ECU is the reference Voltage 5 VDC .

[Zooter]

Might have something to do with being on pod filters?

[docc]

Black. Very tidy mystery.

I have those same connectors-to-nowhere in my factory harness. Red/Black and Blue/Black wires. (not the Black/Violet and Violet of the TPS)

 

No idea what they might be remnants of, but they have never been hooked to anything on my Sport since new . . .

 

EDIT:

Alright, the Red/Black is the power feed to the coils/ injectors /fuel pump from Relay 5 via Fuse 2.  The Blue/Black comes from (or goes to) the ECU, pin 15.

 

What would it have been for?     Certainly not TPS.

[docc]

The Z-plot thickens: I figured the Red/Black would simply show full voltage to the ignition/fuel injection components from Fuse2/Relay 5 with Ignition on/ Run Switch on . . .

 

I switch on and the voltage runs up while the pump primes, then falls off to 8.8 mV. Why wouldn't it just stay at full voltage? Maybe it would if the bike were running and not static?

 

I'm afraid to hook anything to the Blue/Black since that goes into the ECU pin 15 and I don't want to end up like Tron.

[Kiwi_Roy]

It's the warning light connector shown on my schematic as (44)

It should flash a code similar to the P8 ECU

 

 

Sent from my shoe phone!