Dashboard Voltmeter
Thread Starter
Drifting
Joined: Nov 2003
Posts: 1,645
Likes: 65
Dashboard Voltmeter
I've noticed my dashboard voltmeter is giving me a correct reading for about 8-10 V. When I checked the battery voltage at the battery 14.1 volts and the DIC reads correctly. Has anyone seen this problem before and troubleshoot it down, along those lines I noticed the voltmeter does not perform a calibration swing on startup, so I'm inclined to believe it's the controller behind the gauges, but looking for feedback before I tear into it. By the way I have a spare dashboard controller board, so I can do a replacement this winter.
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
LOL! This has been covered several times. The IPC analog volt meter & the digital volt meter does not read battery voltage. It reads the voltage that comes out of the ignition switch for the "HOT IN RUN & START" DC Buss.
When there is a disparity between that meter reading and the actual battery voltage, you most likely have an issue with the contacts inside the ignition switch. There are several contacts inside the ignition and they get burnt and carboned up which cause a voltage drop that you see on the meter.
You can clean those contacts or replace the switch portion of the switch assy.
Bill
When there is a disparity between that meter reading and the actual battery voltage, you most likely have an issue with the contacts inside the ignition switch. There are several contacts inside the ignition and they get burnt and carboned up which cause a voltage drop that you see on the meter.
You can clean those contacts or replace the switch portion of the switch assy.
Bill
Thread Starter
Drifting
Joined: Nov 2003
Posts: 1,645
Likes: 65
LOL! This has been covered several times. The IPC analog volt meter & the digital volt meter does not read battery voltage. It reads the voltage that comes out of the ignition switch for the "HOT IN RUN & START" DC Buss.
When there is a disparity between that meter reading and the actual battery voltage, you most likely have an issue with the contacts inside the ignition switch. There are several contacts inside the ignition and they get burnt and carboned up which cause a voltage drop that you see on the meter.
You can clean those contacts or replace the switch portion of the switch assy.
Bill
When there is a disparity between that meter reading and the actual battery voltage, you most likely have an issue with the contacts inside the ignition switch. There are several contacts inside the ignition and they get burnt and carboned up which cause a voltage drop that you see on the meter.
You can clean those contacts or replace the switch portion of the switch assy.
Bill
Thanks, this just gave me the excuse to go to a push button start, I have done the investigation, install instructions (that I posted), purchased the VAT bypass resistor assembly (easier than buying the connector and resistor) and relay required for key in/out. So I my winter project is now firmed up.
Thanks again
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Don't know if your push button start circuit/assy eliminates the contacts inside the switch or the entire switch but if it doesn't, you will still have the issue.
Bill
Bill
Thread Starter
Drifting
Joined: Nov 2003
Posts: 1,645
Likes: 65
Push button start completely eliminates the ignition switch, uses solid state switches and an added feature of keyless entry.
Le Mans Master
Joined: Jan 2001
Posts: 5,002
Likes: 506
From: Hilton NY
Most DC solid state relays have an internal resistance when on and that can reduce the voltage to the load circuits including the voltmeters. Hopefully there won't be any noticeable drop but you could see 1-2 volts less on the voltmeters and driven circuits.
Thread Starter
Drifting
Joined: Nov 2003
Posts: 1,645
Likes: 65
[QUOTE=Fast one;1597818294]Most DC solid state relays have an internal resistance when on and that can reduce the voltage to the load circuits including the voltmeters. Hopefully there won't be any noticeable drop but you could see 1-2 volts less on the voltmeters and driven circuits.[/QUOTE
Yep checked, the new family of FETs Advanced Keys is using have very low on resistance so the voltage drop is negligible and the heat dissipation is much less, so on both fronts we are good.
Yep checked, the new family of FETs Advanced Keys is using have very low on resistance so the voltage drop is negligible and the heat dissipation is much less, so on both fronts we are good.
Last edited by tentuna; Aug 19, 2018 at 08:20 AM.
