Contour Enthusiasts Group Archives Forums General Troubleshooting Reverse Light Woes

I have an on going issue with my reverse lights, and I am now stuck on what to check. Here is what I have tried.

When the car is in reverse and I am in the trunk checking w/ a test light, no bulbs in the factory light bulb socket, the test light illuminates. When I put the socket w/ bulb back in, no illumination comes from the test light nor the bulb.

When I used a smaller bulb, from a flash light and tested the connections, the reverse lights worked.

I am assuming the reverse lights are getting enough power. What can I test now?

I appreciate any help with this.

This is going to sound dumb, but did you check the bulbs to see if they're blown.
I've bought new blubs that were burnt out before.

From my service manual

CHECK IF SHORT TO GROUND EXISTS IN THE SYSTEM
Disconnect connector K at fuse junction panel.

Disconnect LH and RH backup lamps.

Set the gearshift lever in R (REVERSE).

Using an ohmmeter, measure resistance to ground at fuse junction panel connector Pin K2, Circuit 14 (P/W) - manual transaxle, in Circuit 14 (P/BL) - automatic transaxle.

Is resistance less than 10K ohms?
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CHECK FOR SHORT TO GROUND IN CIRCUIT 14 (P/W)


Disconnect backup lamp switch - manual transaxle, transmission range (TR) sensor - automatic transaxle.

Using an ohmmeter measure resistance to ground in Circuit 14 (P/W) at backup lamp switch connector Pin 1 - manual transaxle, at transmission range (TR) sensor connector Pin 4 - automatic transaxle.

Is resistance less than 10K ohms?


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CHECK FOR SHORT TO GROUND AT BACKUP LAMP SWITCH - MANUAL TRANSAXLE, AT TRANSMISSION RANGE SENSOR - AUTOMATIC TRANSAXLE


Using an ohmmeter measure resistance to ground in Circuit 14S (P/BK) at backup lamp switch connector Pin 2 - manual transaxle, at transmission range (TR) sensor connector Pin 3 - automatic transaxle.
Is resistance less than 10K ohms?

Yes SERVICE short to ground in Circuit 14S (P/BK) or Circuit 14S (P/O). REPLACE Fuse 23 (15A) in fuse junction panel. RESTORE vehicle. RETEST system.
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CHECK BACKUP LAMP SWITCH - MANUAL TRANSAXLE, TRANSMISSION RANGE SENSOR- AUTOMATIC TRANSAXLE


Ignition switch in RUN.

Set the gearshift lever in R (reverse).

Using a voltmeter connected to a good ground check for voltage in Circuit 14S (P/BK) at Pin 2 of backup lamp switch - manual transaxle, at Pin 3 of transmission range (TR) sensor - automatic transaxle.

Is B+ present?
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CHECK FOR VOLTAGE AT BACKUP LAMP


Using a voltmeter connected to a good ground check for voltage in Circuit 14S (P/BK) at backup lamp.

Is B+ present?

Yes
SERVICE ground Circuit 31 (BK) to backup lamps as necessary. RESTORE vehicle. RETEST system.

No
SERVICE Circuit 14S (P/BK) for open. RESTORE vehicle. RETEST system.


Don't ask me what all this stuff means, I don't know. Just giving Ford's service tests.