View Full Version : VSS and NSS Questions
Colonist
07-29-2014, 06:01 AM
Setup: 302 with factory EFI, AOD transmission, A9L, RF wiring harness, GPS speedometer.
1. With the GPS speedometer my first impulse was to plug the VSS hole in the transmission, but won't the ECU require this output? Will the speedometer sender plug in the RF harness also route the VSS signal to the ECU?
2. The RF harness seems to have wiring for the clutch safety switch, but so far I haven't found wiring for a NSS on an auto trans (hit me in the head with it if I've missed it). In the absence of specific wiring for the NSS, can the clutch safety switch wires be rerouted to pins 3 and 4 of the NSS on the transmission?
OCCPete
07-29-2014, 07:42 AM
Your AOD transmission should have a round 4 pin plug on it for the NSS and backup lights:
http://www.mustangandfords.com/how-to/drivetrain/mump-1011-ford-automatic-overdrive-transmission-installation/photo-10.html
I'm not familiar enough with the RF harness to answer your other question.
Colonist
07-29-2014, 09:42 AM
Your AOD transmission should have a round 4 pin plug on it for the NSS and backup lights:
http://www.mustangandfords.com/how-to/drivetrain/mump-1011-ford-automatic-overdrive-transmission-installation/photo-10.html
Yes, that's right. I apologize for my poorly worded question. I've found the 4-pin plug on the transmission, and it is my understanding that pins 1 and 2 are for the backup light, pins 3 and 4 are for the neutral safety switch. Just wondering if the harness wiring for the clutch safety switch wires could be routed through pins 3 and 4 instead of going to the nonexistent clutch pedal.
loeffler1
07-30-2014, 03:23 PM
Maybe I'm crazy, but why would you be searching for clutch safety switch wires on an automatic transmission????
I think he is looking to connect the existing clutch saftey wires from the harness to the neutral safety switch on the trans
Colonist
07-30-2014, 04:10 PM
Setup: 302 with factory EFI, AOD transmission, A9L, RF wiring harness, GPS speedometer.
1. With the GPS speedometer my first impulse was to plug the VSS hole in the transmission, but won't the ECU require this output? Will the speedometer sender plug in the RF harness also route the VSS signal to the ECU?
2. The RF harness seems to have wiring for the clutch safety switch, but so far I haven't found wiring for a NSS on an auto trans (hit me in the head with it if I've missed it). In the absence of specific wiring for the NSS, can the clutch safety switch wires be rerouted to pins 3 and 4 of the NSS on the transmission?
On the off chance that anyone else is interested, here is the result of further research.
1. The ECU does require this output, and the speedometer sender plug in the chassis harness does not route this signal to the ECU. However, the EFI harness also has a plug for the speed sensor that does feed the ECU.
2. The RF chassis harness does not have a plug going to the neutral safety switch, but you can connect the clutch safety switch to the NSS instead (per RF tech guys). Also, in the upper left corner of this wiring diagram http://www.veryuseful.com/mustang/tech/engine/images/88-91_5.0_EEC_Wiring_Diagram.gif , you can see the "clutch engine switch" and the "neutral gear switch" diagrammatically wired in parallel.