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Control module, glow plug (596)

Control module, glow plug (596)

Location

Control module, glow plug (596)

Main task

The task of the glow plug control module is to activate the glow plugs upon the command of the engine management system.

Type

DT/DTH

The control module has a relay output 12V


DTR

The control module has a transistor output 12V PWM.


Connection DT/DTH

Pin No. Signal type Description
1 Output Connected to glow plug cylinder 1 and 2.
2 Output Connected to glow plug cylinder 3 and 4.
3 Power supply +30 Connected to fuse holder 746a.
6 Ground Connected to grounding point G2.
7 Signal Connected to ECM pin 93(B).
8 Diagnostics Connected to ECM pin 52(B).
9 Power supply Via main relay 229. Connects to UEC pin 15(M).



Function DT/DTH

The control module has an internal diagnostic function which monitors the glow plugs. When a fault arises the glow plug control module sends an error message to control module pin 52(B).

When the engine control module pulls pin 93(B) to ground, the glow plug control module is activated, meaning pins 1 and 2 of the control module are supplied voltage.

When voltage on pin 3 (B+) exceeds 12 V, such as when the engine has been started, the control module begins alternately supplying power to pins 1 and 2. Alternation between pins 1 and 2 is done with 5 Hz. The power supply is pulsed alternately to lower power consumption.

Connection DTR

Contact K5

Pin No. Signal type Description
1 Signal. PWM Connected to ECM pin 93(B).
2 Diagnostics Connected to ECM pin 52(B).
3 Ground Connected to grounding point G2.
4 Power supply Via main relay 229. Connects to UEC pin 15(M).
5 Power supply +30 Connected to fuse holder 746a.


Diagram, contact K5


Contact K6

Pin No. Signal type Description
1 Power supply PWM Connected to glow plug 398b cylinder 2
2 - -
3 Power supply PWM Connected to glow plug 398a cylinder 1
4 Power supply PWM Connected to glow plug 398c cylinder 3
5 - -
6 Power supply PWM Connected to glow plug 398d cylinder 4


Diagram, contact K6


Function DTR

The control module has an internal diagnostic function which monitors the glow plugs. When a fault arises the glow plug control module sends an error message to control module pin 52(B).

When the engine control module switches pin 93(B) to ground, the glow plug control module is activated. At which point one glow plug is energised at a time by a PWM voltage, the frequency of which is 35 Hz and voltage is B+, in order that average voltage should not exceed 4.4 V. This is in order to reduce the total power consumption.

As battery voltage is never below the rated voltage of 4.4 V for the glow plugs they always receive full output during the engagement period.