Subject: [TR] Back-up Light Circuit on a 72 TR6

From: [email-masked]
Date: Sat, 13 Jul 2013 20:53:37 +0000 (UTC)

Could someone talk me through the back-up light circuit on a 72 TR6? I can't get the car inspected unless all the lights work, and the Summer's slipping away faster than I can imagine! 

Here's where I am with this project: 

I have taken the transmission cover out of the car and have determined that with the key in the "run" position I am not getting power to the switch on the side of the top cover of the transmission. The connections between the switch and the rest of the circuit (where they connect to allow removal of the transmission tunnel) are also "dead" 

I have looked at the diagram on page 488 of the Bentley's manual, but am confused by some of the symbols that I find in the circuit (found at the bottom of the diagram on the right side.) It seems that before the power-in wire connects to the seatbelt warning, gearbox switch (#66 - and what is that and where in the car is it?) there is a resistor in the wire (indicated by a rectangle in the line). From there, the line goes to the reverse lamp switch (#34) and from there to another resistor, then to a light (the circle with an "X") in it) and finally to the 2 lamps in the rear lamp housing (#35). Do I understand the symbols correctly? Is a rectangle a resistor? Is a circle with an "X" really a bulb? If so, where are they physically in the car? And where should I look to find the break in continuity before the switch? 

I'm usually pretty good at figuring electrical problems out, but this one has me stumped. I know that there are some listers who live for sorting out problems-Lucas, so I'm throwing myself at your feet - HELP! 

Tom Walling 

** [email-masked] **

Archive: http://www.team.net/archive

---

From: "Bob" <[email-masked]>
Date: Sat, 13 Jul 2013 17:48:58 -0400 R768guEB15FYQ8/q1+LMmlFGwRlL+V7a/Cke4uGjFFJSsEbpka b2kndvQ52QPY4u1OT6zi9Mnmu72/xvCtD9WXtg/1F1Vojfm7PD RHcoHQmJcSWQagoApjaZorJU5RMVmt4hYPVY1N6cgv8agXBm+E VYSGvU6+kFckW6pP6nwsCBS5/RfBCxkLKAtjq1VDDNxBG8vVpq Zo/kHGBVK3iPDxqy/qxx0Z7lMxa/n/HZ160wbS+KjEazZ/Yi9P bMCmH4xNew4QMm2GYOoIqrFJ7l3UNgzDlwsjlukOzBAmQavzKb l5oMQduv7fGOziyHO2wgC41Qa8aWBzcVSCAK+NWXY

The first thing you want to do is download 
(http://www.advanceautowire.com/tr2506.pdf) the free AAW schematics that Dan 
Masters developed about 10 years ago with input from many list members. This 
is a much more accurate schematic and is specific to model year. The other 
thing that is a great help is Dan's Electrical Maintenance Handbook 
available from Moss. Besides step by step trouble shooting it includes a 
section on all of the symbols.

As I'm looking at the schematic the reverse light power is on the power side 
of the seatbelt neutral switch so the switch doesn't impact its operation.

- rectangle box =  bullet connector
- circle w/ X = 1 pin of a multi pin connector for the main to rear harness. 
Located near the floor on driver's side
- circle that's solid = splice

Bob

Bob Danielson
http://tr6.danielsonfamily.org/

1975 TR6 modified with:
-Throttle Body Injection
-Toyota 5 Speed
-Nissan Differential
-AAW Wire Harness
-CVJs... and more

-----Original Message----- 
From: [email-masked]
Sent: Saturday, July 13, 2013 4:53 PM
To: NET Member Mailing ; Triumphs
Subject: [TR] Back-up Light Circuit on a 72 TR6

Could someone talk me through the back-up light circuit on a 72 TR6? I can't 
get the car inspected unless all the lights work, and the Summer's slipping 
away faster than I can imagine!

I have taken the transmission cover out of the car and have determined that 
with the key in the "run" position I am not getting power to the switch on 
the side of the top cover of the transmission. The connections between the 
switch and the rest of the circuit (where they connect to allow removal of 
the transmission tunnel) are also "dead"

I have looked at the diagram on page 488 of the Bentley's manual, but am 
confused by some of the symbols that I find in the circuit (found at the 
bottom of the diagram on the right side.) It seems that before the power-in 
wire connects to the seatbelt warning, gearbox switch (#66 - and what is 
that and where in the car is it?) there is a resistor in the wire (indicated 
by a rectangle in the line). From there, the line goes to the reverse lamp 
switch (#34) and from there to another resistor, then to a light (the circle 
with an "X") in it) and finally to the 2 lamps in the rear lamp housing 
(#35). Do I understand the symbols correctly? Is a rectangle a resistor? Is 
a circle with an "X" really a bulb? If so, where are they physically in the 
car? And where should I look to find the break in continuity before the 
switch?

I'm usually pretty good at figuring electrical problems out, but this one 
has me stumped. I know that there are some listers who live for sorting out 
problems-Lucas, so I'm throwing myself at your feet - HELP!

Tom Walling

Archive: http://www.team.net/archive
http://autox.team.net/mailman/options/triumphs/[email-masked]