Date: Thu, 12 Aug 1999 17:31:31 -0400
Reply-To: Noto-Gaudette <derwin@NET1PLUS.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Noto-Gaudette <derwin@NET1PLUS.COM>
Subject: Re: Blinking Red Light--solved?
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Thanks to Steve Macaulay, I was able to find two technical service
bulletins relating to "the little red light." Both offer info that is
new to me. I'll report back.
BTW, the microfiche referred to below is probably the Bentley on
microfiche, which sells for $25 from VW pub's. If you have a fiche
reader (I do, but for no reason yet) you could save some bucks on ol'
Bentley...but geez, can you imagine hauling around a fiche reader? <g>
Technical Bulletin
Group: 90
Number: 92-03
Date: February 29, 1992
Subject: Coolant Indicator LED is Flashing at Normal Temperatures
Model(s): All Models
CONDITION
Coolant overheat / low coolant level indicator LED is flashing at
normal coolant temperatures.
SERVICE
Check the coolant indicator LED according to the list below.
The following applies IN ADDITION to tests listed in the Service
Microfiche. .
* refer to appropriate wiring diagram
* disconnect coolant level sensor electrical connector
* check coolant level in coolant reservoir
*** MUST be between MIN and MAX marks
* set digital multimeter, Fluke 83 (US 1119) to ohms function
* check resistance of level sensor with digital multimeter Fluke 83
(US 1119)
*** must be between 31K Ohm and 65K Ohm with correct COOLANT LEVEL
AND COOLANT CONCENTRATION.
NOTE
If coolant resistance is NOT within the above specifications, the
coolant MUST be drained and replaced with NEW coolant mixture of
50 percent water and 50 percent phosphate free coolant antifreeze,
Part No. ZVW 237 104. (In Canada, use Part No. G 001 100). The
mixing should be performed before filling vehicle cooling system.
*****************************************************************
* CAUTION *
* Coolant concentrations of 60 percent or higher will cause the *
* overtemp / low coolant LED to activate. *
****************************************************************
*****************************************************************
* CAUTION *
* Coolant antifreeze MUST NOT be reused. Properly dispose of *
* used coolant. *
****************************************************************
* reconnect sensor connector
* check coolant level control unit using wiring diagram
NOTE
The control unit is located on top of the fuse/relay panel on vehicles
up to 1989 model year and thereafter it is integrated into the multi-
processor of the instrument cluster circuit board.
* if wiring, coolant level sensor and coolant concentration are OK,
replace coolant level control unit or instrument cluster circuit
board
* refer to appropriate Service Microfiche Group 90 - Coolant
Temperature Gauge, checking and troubleshooting
* confirm proper operation of temperature gauge and blinking LED per
Service Microfiche Group 90
*****************************************************************
* CAUTION *
* Part Numbers are for reference only. Always check with your *
* Parts Department for latest parts information. *
****************************************************************
=======================================================================
Technical Information
Group: 90
Number: 87-03
Date: July 31, 1987
Subject: Coolant Temperature Gauge Light flashes
intermittently / continuously
Model(s): All Models, all Model Years
Flashing coolant temperature light may be caused by:
- Low coolant level.
- Coolant level indicator.
- Electrical connections on gauge.
* Check coolant level, top up if necessary.
* Check coolant level sensor for continuity.
* Check for loose connection of wiring at terminal 14 connectors of
instrument cluster, nuts of temperature gauge, ground connection
to body and engine ground. Repair if necessary.
If temperature gauge light still flashes:
* Replace low coolant level control unit
=======================================================================