Automatic Glow Time Control Module -J179- AND GLOW PLUGS, CHECKING

Observe all safety precautions: SAFETY PRECAUTIONS 

View clean working conditions: CLEAN WORKING CONDITIONS 

Prior to repair work, perform a preliminary check to verify the condition. Refer to PRELIMINARY CHECK .

Use only gold-plated terminals when servicing any component with gold-plated electrical harness connector terminals.

For wiring diagrams, component locations, and connector views, Refer to the applicable wiring diagram.

Special tools and workshop equipment required 

• Multimeter
• Wiring diagram

Test Requirements 

• A/C switched off
• All electrical consumers switched off
• Battery voltage at least 12.5 volts
• Engine control module fuses OK
• Ground connections between engine/transmission/chassis OK
• Ignition switched off
• Vehicles with automatic transmission, shift selector lever in park or neutral

Start diagnosis

-- The Automatic Glow Time Control Module -J179- is a relay located in the underhood fuse box and can be viewed by removing the cover of the fuse box and remove the automatic glow time control module (relay A3).

-- Disconnect the Automatic Glow Time Control Module -J179- (relay) connector.

Checking voltage

Ignition switched ON.

-- Using a multimeter with BLACK lead connected to engine ground, measure the voltage of terminal 11 (relay terminal 30) and then 5 (relay terminal 87) of the Automatic Glow Time Control Module -J179- black (relay) harness connector.

Specified value for each terminal: Battery voltage.

If the specified value was obtained:

-- Using a multimeter with the RED lead connected to Battery voltage, measure the ground of terminal 7 (relay terminal 31) of the Automatic Glow Time Control Module -J179- black (relay) harness connector.

Specified value: Battery voltage.

Ignition switched OFF.

If the any of the specified values were not obtained:

-- Check the circuit for an short to ground, open or high resistance.

-- Check the electrical harness connector for damage, corrosion, loose or broken terminals.

-- Replace any blown fuses.

-- Repair as necessary.

If the specified value was obtained:

Ignition switched ON.

-- Using a multimeter with BLACK lead connected to engine ground, measure the voltage at terminal 10 (relay terminal ST) of the Automatic Glow Time Control Module -J179- black (relay) harness connector.

Specified value: 3.44 V (+/-.5 V)

If the specified value was obtained:

-- Using a multimeter with BLACK lead connected to engine ground, measure the voltage at the terminal 9 (relay terminal D1) of the Automatic Glow Time Control Module -J179- black (relay) harness connector.

Specified value: 10.74 V (+/-.8 V)

If the voltage readings were correct:

Ignition switched OFF.

-- Replace the Automatic Glow Time Control Module -J179- (relay).

If any of the specified values were not obtained:

-- Remove the Engine Control Module -J623-. Refer to the Repair Manual.

-- Using a multimeter, check the Automatic Glow Time Control Module -J179- electrical harness connector to the Engine Control Module -J623- electrical harness T91 connector for resistance.

Remove Positive battery cable when testing resistance on these circuits.

Automatic Glow Time Control Module -J179- electrical harness (black) connector T11 terminal :	Engine Control Module -J623- electrical harness connector T91 terminals or specified location
11	to Battery positive terminal
10	58
9	42
7	to Body Ground
6	The appropriate fuse. Refer to applicable wiring diagram for fuse positions

Specified value: 1.5 Ω Max.

If the specified value was Not obtained:

-- Check the wiring for a short circuit to each other, Battery voltage, Ground or high resistance.

-- If necessary, repair the faulty wiring connection.

-- Check the electrical harness connector for damage, corrosion, loose or broken terminals.

If no malfunction is detected in the wiring and the voltage readings were Not correct:

-- Replace the Engine Control Module -J623-. Refer to the service information for removal and installation procedures.

Checking Glow Plugs

Engine must be cool to touch or resistance values will be affected.

-- Using a multimeter, check the resistance of each glow plug at the Automatic Glow Time Control Module -J179- black (relay) harness connector to engine ground (with the glow plugs connected). These are identified as 1, 2. 3, 4, 5, 8 on the black (relay) harness connector (or G1 - G6 identified on relay) and correspond to Glow Plug 1, 2, 3, 4, 5, 6.

Specified value: 1.3 Ω Max. each glow plug (0.6 Ω for Glow Plug, 0.2 Ω for wiring).

If the specified value was not obtained:

-- Check the glow plug or circuit for a short, open circuit or high resistance.

-- Check the electrical harness connector for damage, corrosion, loose or broken terminals.

-- Repair/replace as necessary.

Final Procedures 

After repair work, the following work steps must be performed in the following sequence:

1. Check the DTC memory. Refer to DIAGNOSTIC MODE 03 - READ DTC MEMORY .
2. If necessary, erase the DTC memory. Refer to DIAGNOSTIC MODE 04 - ERASE DTC MEMORY .
3. If the DTC memory was erased, generate readiness code. Refer to READINESS CODE .