Topic: IVR Test

[koski19]

Is there any way to test an Internal Voltage Regulator?
I used my auto ranging volt meter and on the Ohm setting it showed OL on the meter
which tells me the IVR needed to be replaced.

Jeff

[CharlesTurner]

Probably information in the Ford shop manual that would help with this.  If you don't have a copy, would highly recommend you purchase one.

[jwc66k]

Depending on what year you have (it's a good idea to include that in any post), you have at least two gages that use the 5 volts the low voltage regulator puts out. There are two main causes for it to fail, the contacts are fused, or the heating coil opened (burnt out). A bench top resistance reading across the two terminals will read zero ohms, which is the normal unpowered state. Take a reading from the female spade connection to the regulator case and you should get a low resistance reading which indicate that the coil is OK. The in-car test requires access to the regulator usually mounted on the back oft he instrument cluster, and with the ignition switch to accessories, you should get a reading of about 5 volts (it may go up to 10) on the input connection lead (black-green stripe) to the fuel gage. Most of the time, if the regulator was thought to be defective, it was replaced.
Jim   

[sah62]

If you're asking about the IVR used behind the instrument cluster I posted test procedures on the VMF a few years ago:

http://forums.vintage-mustang.com/vintage-mustang-forum/493976-instrument-panel-voltage-reg.html#post3082029

[midlife]

If you're asking about the IVR used behind the instrument cluster I posted test procedures on the VMF a few years ago:

http://forums.vintage-mustang.com/vintage-mustang-forum/493976-instrument-panel-voltage-reg.html#post3082029

Yup, the old analog voltage meters are a must, as the digital volt-ohm meters react too quickly for the slow IVR voltage changes. 

Another issue that can cause you to think the IVR is bad are crappy connectors to the IVR: the molded connectors themselves...ask me how I know!

[koski19]

Depending on what year you have (it's a good idea to include that in any post), you have at least two gages that use the 5 volts the low voltage regulator puts out. There are two main causes for it to fail, the contacts are fused, or the heating coil opened (burnt out). A bench top resistance reading across the two terminals will read zero ohms, which is the normal unpowered state. Take a reading from the female spade connection to the regulator case and you should get a low resistance reading which indicate that the coil is OK. The in-car test requires access to the regulator usually mounted on the back oft he instrument cluster, and with the ignition switch to accessories, you should get a reading of about 5 volts (it may go up to 10) on the input connection lead (black-green stripe) to the fuel gage. Most of the time, if the regulator was thought to be defective, it was replaced.
Jim

Ooops.....It's a 66 with gauges......Thanks for the info......This will need to wait until the car is back together.........Jeff

[koski19]

If you're asking about the IVR used behind the instrument cluster I posted test procedures on the VMF a few years ago:

http://forums.vintage-mustang.com/vintage-mustang-forum/493976-instrument-panel-voltage-reg.html#post3082029

Thanks for the link...It's now in Favorites.........jeff