07-06-2022, 03:08 PM | #1 |
Registered User
Join Date: Apr 2016
Location: saginaw Mi.
Posts: 70
|
Tachometer
Help please, my tach stopped working after getting my truck buried in a mud hole. It is 2001 2500 HD 8.1
I'm not sure if there are any wires underneath the truck that may have gotten damaged? I am not sure where to start. Thank you |
07-10-2022, 05:04 PM | #2 |
Moderator
Join Date: Oct 2008
Location: Wentworth, NH
Posts: 4,977
|
Re: Tachometer
This is likely an "and this failed too".
The tach is driven from the engine speed signal out of the PCM. It's a white wire at the cluster plug IIRC. It's a digital signal. You can check the signal with an oscilloscope but don't plug a meter or anything else into it. The PCM should be reasonably protected in the engine bay and I'd expect other stuff to stop working if the PCM wiring got damaged. The 2001 uses air core motors not steppers like the 2003-2007. Usually the air core gauge motors don't fail but sometimes the electronics get flaky.
__________________
1959 M35A2 LDT465-1D SOLD 1967 Dodge W200 B383, NP420/NP201 SOLD 1969 Dodge Polara 500 B383, A833 SOLD 1972 Ford F250 FE390, NP435/NP205 SOLD 1976 Chevy K20, 6.5L, NV4500/NP208 SOLD 1986 M1008 CUCV SOLD 2000 GMC C2500, TD6.5L, NV4500 2005 Chevy Silverado LS 2500HD 6.0L 4L80E/NP263 2009 Impala SS LS4 V8 RTFM... GM Parts Books, GM Schematics, GM service manuals, and GM training materials...
And please let us know if and how your repairs were successful. Last edited by hatzie; 07-10-2022 at 05:12 PM. |
07-11-2022, 10:21 AM | #3 |
Registered User
Join Date: Apr 2016
Location: saginaw Mi.
Posts: 70
|
Re: Tachometer
Thank you very much!!
|
Bookmarks |
|
|